WO2018006545A1

WO2018006545A1 - Read and write method and apparatus for sd card

Info

Publication number: WO2018006545A1
Application number: PCT/CN2016/108603
Authority: WO
Inventors: 叶甘临
Original assignee: 中兴通讯股份有限公司
Priority date: 2016-07-08
Filing date: 2016-12-05
Publication date: 2018-01-11
Also published as: CN107589904A; CN107589904B

Abstract

Disclosed are a read and write method and apparatus for an SD card. The read and write method for an SD card comprises: when it is determined that an SD card to be read and written is a pre-set SD card, determining whether a device, into which the SD card to be read and written is inserted, writes data in a memory into at least one pre-set SD card before the SD card to be read and written is accessed (S11); if the data is written into the at least one pre-set SD card, taking the least one pre-set SD card as a target SD card (S12); determining whether the SD card to be read and written is the target SD card (S13); and if the SD card to be read and written is the target SD card, saving data which has been written into the SD card to be read and written, and writing the data, which has not been unwritten, in the memory of the device into a first directory of the SD card to be read and written (S14). The method can write, when a previously removed SD card is inserted again, data, which has not been written, in a memory of a device into same, which improves the data read and write accuracy and avoids data loss, thereby effectively improving the user experience.

Description

SD card reading and writing method and device

Technical field

The embodiments of the present invention relate to the field of software development technologies, and in particular, to a method and an apparatus for reading and writing an SD card.

Background technique

When a user inserts an SD card to be read and written using an electronic device, there is a need to expand the internal storage space of the electronic device. In the related art, the SD card to be read and written is formatted as an internal storage device, and the media file of the inserted device internal storage space is moved to the SD card to be read and written, and the directory for storing the media file inside the inserted device is Uninstall.

In this way, the SD card to be read and written is removed from the inserted device, and the directory for storing the media file inside the inserted device is not remounted. In this case, the application that needs to store the media file has no place to store the file. , causing it to be unusable.

Summary of the invention

The embodiments of the present invention aim to solve at least one of the technical problems in the related art to some extent.

Therefore, an object of the embodiment of the present invention is to provide a method for reading and writing an SD card, which can write data that has not been written in the memory of the device when the SD card is removed before reinsertion, thereby improving data reading and writing. Accuracy, avoid data loss, and effectively improve the user experience.

Another object of the embodiments of the present invention is to provide a read/write device for an SD card.

In order to achieve the above object, the method for reading and writing an SD card according to the first aspect of the present invention includes: determining that the device to be read and written by the SD card is connected when determining that the SD card to be read and written is a preset SD card Whether to write data in the memory to at least one preset SD card before entering the SD card to be read or written; if the data is written into the at least one preset SD card, At least one preset SD card is used as the target SD card; determining whether the SD card to be read and written is the target SD card; if the SD card to be read and written is the target SD card, saving The data that has been written in the SD card to be read and written, and the data that has not been written in the memory of the device is written into the first directory in the SD card to be read and written.

In an embodiment of the present invention, the method further includes: detecting whether the SD card to be read and written is removed from the device; if the SD card to be read and written is not removed from the device, the data is When the writing is completed, the second directory in the device is uninstalled, wherein the second directory is a storage directory in which the data is written in the memory of the device before the data is written to the SD card to be read or written. Changing a path in the device that locates the second directory to a path that locates the first directory.

In an embodiment of the present invention, after detecting whether the SD card to be read or written is removed from the device, the method further includes: if the SD card to be read and written is removed from the device, determining to remove Whether the data in the memory has been written to the SD card to be read and written before the SD card to be read or written; if the data in the memory has been written into the SD card to be read and written, the mount Describe a second directory, and change a path in the device that locates the first directory to the path that locates the second directory.

In an embodiment of the present invention, determining, by the following step, that the SD card to be read and written is the preset SD card: acquiring a preset identifier of the SD card to be read and written; detecting the preset identifier in the Whether there is a record in the inserted device; if the preset identifier has the record in the inserted device, it is determined that the SD card to be read and written is the preset SD card.

In an embodiment of the present invention, after detecting whether the preset identifier has a record in the inserted device, the method further includes: if the preset identifier does not exist in the inserted device, And formatting the SD card to be read and written.

The method for reading and writing an SD card according to the first aspect of the present invention saves the data written in the SD card to be read and written when the SD card to be read or written is the target SD card, and the memory of the device is not yet written. The entered data is written in the first directory of the SD card to be read and written, and the data that has not been written in the memory of the device can be written into the SD card that is removed before being inserted again, thereby improving the read/write accuracy of the data and avoiding Data loss, effectively improve the user experience.

In order to achieve the above object, the SD card reading and writing device according to the second aspect of the present invention is The method includes: a first determining module, configured to determine, when determining that the SD card to be read or written is a preset SD card, whether the device inserted in the SD card to be read or written is in the memory before accessing the SD card to be read or written Data is written into at least one preset SD card; the first processing module is configured to set the at least one preset SD when the data is written into the at least one preset SD card The card is used as the target SD card; the second determining module is configured to determine whether the SD card to be read and written is the target SD card; and the saving module is configured to: when the SD card to be read and written is the target SD card, The data written in the SD card to be read and written is saved, and data not yet written in the memory of the device is written in the first directory in the SD card to be read and written.

In an embodiment of the present invention, the method further includes: a first detecting module, configured to detect whether the SD card to be read and written is unplugged from the device; and the uninstalling module is configured to not read the SD to be read or written When the card is detached from the device, when the data is written, the second directory in the device is uninstalled, wherein the second directory is written before the data is written to the SD card to be read and written. Determining a storage directory of data in a memory of the device; a change module configured to change a path in the device that locates the second directory to a path to locate the first directory.

In an embodiment of the present invention, the method further includes: a third determining module, configured to determine, when the SD card to be read or written is removed from the device, whether the SD card to be read or written is removed The data in the memory is written into the SD card to be read and written; the mounting module is configured to mount the second directory when data in the memory has been written to the SD card to be read and written, and Changing a path in the device that locates the first directory to the path that locates the second directory.

In an embodiment of the present invention, whether the SD card to be read or written is the preset SD card is determined by the following module: an acquiring module, configured to acquire a preset identifier of the SD card to be read and written; and second detecting a module, configured to detect whether the preset identifier has a record in the inserted device, and a second processing module configured to determine, when the preset identifier exists in the inserted device, The SD card to be read and written is the preset SD card.

In an embodiment of the present invention, the second processing module is further configured to format the SD card to be read and written when the preset identifier does not exist in the inserted device. deal with.

In the embodiment of the present invention, a computer storage medium is further provided, and the computer storage medium may store an execution instruction for executing the read/write method of the SD card in the foregoing embodiment.

The read/write device for the SD card according to the second embodiment of the present invention saves the data written in the SD card to be read and written when the SD card to be read or written is the target SD card, and the memory of the device is not yet written. The entered data is written in the first directory of the SD card to be read and written, and the data that has not been written in the memory of the device can be written into the SD card that is removed before being inserted again, thereby improving the read/write accuracy of the data and avoiding Data loss, effectively improve the user experience.

The additional aspects and advantages of the invention will be set forth in part in the description which follows.

DRAWINGS

The above and/or additional aspects and advantages of the present invention will become apparent and readily understood from

1 is a schematic flow chart of a method for reading and writing an SD card according to an embodiment of the present invention;

2 is a schematic flow chart of a method for reading and writing an SD card according to another embodiment of the present invention;

3 is a schematic flow chart of a method for reading and writing an SD card according to another embodiment of the present invention;

4(a) is a schematic diagram of a path for a device to locate a first directory in an embodiment of the present invention;

4(b) is a schematic diagram showing the path of the second directory of the device in the embodiment of the present invention;

FIG. 5 is a schematic structural diagram of a read/write device for an SD card according to an embodiment of the present invention; FIG.

FIG. 6 is a schematic structural diagram of a read/write device for an SD card according to another embodiment of the present invention.

detailed description

The embodiments of the present invention are described in detail below, and the examples of the embodiments are illustrated in the drawings, wherein the same or similar reference numerals are used to refer to the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the drawings are exemplified and are only used to explain the present invention. The invention is not to be construed as limiting the invention. Rather, the invention is to cover all modifications, modifications and equivalents within the spirit and scope of the appended claims.

FIG. 1 is a schematic flow chart of a method for reading and writing an SD card according to an embodiment of the present invention. The reading and writing method of the SD card is configured as an SD card reading and writing device as an example. Embodiments of the present invention can be applied in a process in which a user inserts an SD card using an electronic device.

Referring to FIG. 1, the method for reading and writing the SD card includes the following steps:

S11: When determining that the SD card to be read or written is a preset SD card, determining whether the device inserted into the SD card is to write the data in the memory to at least one preset SD card before accessing the SD card to be read or written. in.

In the embodiment of the present invention, the SD card to be read and written is an SD card that the user needs to read and write.

The executor of this embodiment is a device that can be inserted into an SD card to be read and written, wherein the device to be read and written by the SD card is an electronic device having a function of inserting an SD card to be read and written, for example, a mobile terminal or a personal computer (Personal Computer) , PC), etc., there is no limit to this.

The mobile terminal may be a hardware device with various operating systems, such as a smart phone, a tablet computer, a personal digital assistant, and an e-book.

In the embodiment of the present invention, after establishing a communication connection between the SD card to be read and written and the inserted device, determining whether the SD card to be read or written is a preset SD card, and when the SD card to be read and written is a preset SD card And determining whether the device to be read and written by the SD card inserts the data in the memory into the at least one preset SD card before accessing the SD card to be read or written, to trigger the subsequent step.

In some embodiments, referring to FIG. 2, the embodiment of the present invention may determine whether the SD card to be read or written is a preset SD card by using the following steps. The execution body of this embodiment is a device that can be inserted into the SD card to be read and written, including :

S21: Obtain a preset identifier of the SD card to be read and written.

In the embodiment of the present invention, the preset identifier may be fsUuid, where Uuid is a Universally Unique Identifier (Uuid), and its format is, for example, 1234-ABCD. Or, partGuid, where the Guid is a Globally Unique Identifier (Guid), and the format is, for example, xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx, where each x is a range of 0-9 or af. 4-digit hexadecimal number.

S22: Detect whether the preset identifier has a record in the inserted device, and if yes, execute S24; otherwise, execute S23.

Optionally, for example, detecting whether a partGuid of the SD card to be read or written has a record in the inserted device, and if there is a record, determining whether the fsUuid recorded by the mPrimaryStorageUuid in the inserted device is equal to the fsUuid of the SD card to be read and written, If the two are equal, it is confirmed that the preset ID has a record in the inserted device.

Optionally, detecting whether the preset identifier has a record in the inserted device to trigger a subsequent step.

S23: Formatting the SD card to be read and written.

Optionally, when the preset identifier does not have a record in the inserted device, the SD card to be read and written is formatted.

S24: Determine that the SD card to be read and written is a preset SD card.

Optionally, when the preset identifier has a record in the inserted device, determining that the SD card to be read and written is a preset SD card.

In this embodiment, when the record is detected in the inserted device by detecting the preset identifier, it is determined that the SD card to be read and written is a preset SD card, and the device that can be conveniently inserted is subjected to subsequent processing, thereby effectively improving the user experience.

S12: If the data is written into at least one preset SD card, at least one preset SD card is used as the target SD card.

Optionally, when the device to be read or written by the SD card is inserted into the at least one preset SD card before accessing the SD card to be read or written, at least one preset SD card is used as the preset SD card. The target SD card indicates that the device to be read and written by the SD card inserts the data in the memory to the target SD card before accessing the SD card to be read or written.

S13: Determine whether the SD card to be read or written is a target SD card.

Optionally, by determining whether the SD card to be read or written is a target SD card, it can be learned whether the inserted device moves the data in the memory to the SD card to be read and written before the SD card to be read or written is accessed, to trigger subsequent step.

S14: If the SD card to be read and written is the target SD card, save the data that has been written in the SD card to be read and written, and write the data that has not been written in the memory of the device into the first directory in the SD card to be read and written. under.

In an embodiment of the invention, the first directory is a storage directory of data in the memory of the SD card to be read and written, for example, the /mnt/expand/fsUuid directory.

Optionally, when the SD card to be read or written is the target SD card, it indicates that the device to be read and written by the SD card has written part of the data in the memory into the SD card to be read and written before accessing the SD card to be read and written. At this time, the data that has been written in the SD card to be read and written is saved, and the data that has not been written in the memory of the device is written in the first directory in the SD card to be read and written, for example, the memory of the device is not yet written. The data is written to the /mnt/expand/fsUuid directory.

In some embodiments, referring to FIG. 3, the method for reading and writing the SD card may further include:

S31: Detect whether the SD card to be read or written is removed from the device, and if yes, execute S34; otherwise, execute S32.

Optionally, it is detected whether the SD card to be read and written is removed from the device to trigger a subsequent step.

S32: When the data is written, the second directory in the device is unloaded, wherein the second directory is a storage directory in which the data is written in the memory of the device before the data is written to the SD card to be read or written.

In the embodiment of the present invention, the second directory is a storage directory in which data is written in the memory of the device before the data is written to the SD card to be read and written, for example, the /data/media directory.

Optionally, when the SD card to be read or written is not removed from the device, when the data is written, the second directory in the device is uninstalled, that is, the second directory is in an uninstall state.

S33: Change the path of the second directory in the device to the path of the first directory.

Optionally, changing a path for locating the second directory in the device to a path for locating the first directory, That is, the first directory is in the mounted state, the second directory is in the unloading state, and the path of the first directory is located in the device, and the SD card to be read and written can be mounted when the data is written, and the storage space of the inserted device is expanded.

As an example, referring to FIG. 4(a), the /storage/emulated directory is the path for storing data in the upper layer. When the SD card to be read or written is not removed from the device, the /mnt/expand/fsUuid directory is mounted. The /data/media directory is unloaded. At this point /storage/emulated points to /mnt/expand/fsUuid.

S34: It is judged whether the data in the memory has been written into the SD card to be read and written before the SD card to be read or written is removed.

Optionally, when the SD card to be read or written is removed from the device, it is determined whether the data in the memory has been written into the SD card to be read and written before the SD card to be read or written is removed, to trigger the subsequent step.

S35: If the data in the memory has been written to the SD card to be read and written, the second directory is mounted, and the path of the first directory in the device is changed to the path for locating the second directory.

Optionally, when the data in the memory has been written into the SD card to be read and written, the second directory is mounted, and the path of the first directory in the device is changed to the path for locating the second directory, that is, the second directory is In the mounted state, the first directory is in the unloaded state, and the path of the second directory is located in the device. The internal storage space of the device can be re-mounted when the SD card to be read or written is removed, and the application that needs to store the media file is guaranteed to operate normally.

As an example, referring to FIG. 4(b), when the SD card to be read or written is removed from the device, the /mnt/expand/fsUuid directory is in the uninstall state, and the /data/media directory is in the mount state. At this time, /storage /emulated points to /data/media.

In this embodiment, when the SD card to be read or written is not removed from the device, when the data is written, the second directory in the device is uninstalled, and the path of the second directory in the device is changed to the first location. The directory path can mount the SD card to be read and written when the data is written, and expand the storage space of the inserted device without affecting the use of the originally installed application. The SD card to be read and written is removed from the device. When the data in the memory has been written to the SD card to be read and written, the second directory is mounted, and the path of the first directory in the device is changed to the path for locating the second directory. Re-mount the internal storage space of the device when the SD card to be read or written is removed. This ensures that the application that needs to store media files runs normally and improves the user experience.

In this embodiment, when the SD card to be read or written is the target SD card, the data that has been written in the SD card to be read and written is saved, and the data that has not been written in the memory of the device is written into the SD card to be read and written. In the first directory, the SD card that was unplugged before being inserted again can write data that has not been written in the memory of the device, thereby improving the read/write accuracy of the data, avoiding data loss, and effectively improving the user experience.

FIG. 5 is a schematic structural diagram of an apparatus for reading and writing an SD card according to an embodiment of the present invention. The read/write device 500 of the SD card can be implemented by software, hardware, or a combination of both.

Referring to FIG. 5, the read/write device 500 of the SD card may include: a first determining module 501, a first processing module 502, a second determining module 503, and a saving module 504. among them,

The first determining module 501 is configured to determine, when determining that the SD card to be read or written is a preset SD card, whether the device inserted into the SD card is to write at least one of the data in the memory before accessing the SD card to be read or written. Zhang's preset SD card.

The first processing module 502 is configured to set at least one preset SD card as the target SD card when writing data into at least one preset SD card.

The second determining module 503 is configured to determine whether the SD card to be read or written is a target SD card.

The saving module 504 is configured to save the data that has been written in the SD card to be read and written when the SD card to be read and written is the target SD card, and write the data that has not been written in the memory of the device into the SD card to be read and written. The first directory.

In some embodiments, referring to FIG. 6, the read/write device 500 of the SD card may further include:

The first detecting module 505 is configured to detect whether the SD card to be read and written is removed from the device.

The unloading module 506 is configured to, when the SD card to be read or written is not removed from the device, uninstall the second directory in the device when the data is written, wherein the second directory is to write data to the SD card to be read and written. The directory where the data is stored in the device's memory.

The change module 507 is configured to change the path of the second directory located in the device to the first position The path to the directory.

The third determining module 508 is configured to determine whether the data in the memory has been written into the SD card to be read or written before the SD card to be read or written is removed, when the SD card to be read or written is removed from the device.

The mounting module 509 is configured to mount the second directory when the data in the memory has been written to the SD card to be read and written, and change the path of the first directory in the device to the path for locating the second directory.

Optionally, whether the SD card to be read or written is a preset SD card is determined by the following modules:

The obtaining module 510 is configured to obtain a preset identifier of the SD card to be read and written.

The second detecting module 511 is configured to detect whether the preset identifier has a record in the inserted device.

The second processing module 512 is configured to determine that the SD card to be read and written is a preset SD card when the preset identifier exists in the inserted device, and to read and write when the preset identifier does not exist in the inserted device. The SD card is formatted.

It should be noted that the description of the method for reading and writing the SD card in the foregoing embodiments of FIG. 1 to FIG. 4 is also applicable to the read/write device of the SD card of the embodiment, and the implementation principle thereof is similar, and details are not described herein again. .

It should be noted that in the description of the present invention, the terms "first", "second" and the like are used for descriptive purposes only, and are not to be construed as indicating or implying relative importance. Further, in the description of the present invention, the meaning of "a plurality" is two or more unless otherwise specified.

Any process or method description in the flowchart or otherwise described herein can be understood to represent an executable that includes one or more steps for implementing a particular logical function or process. Modules, segments or portions of code of instructions, and the scope of preferred embodiments of the invention includes additional implementations, which may not be in the order shown or discussed, including in a substantially simultaneous manner or vice versa depending on the functionality involved. The order is to perform the functions, which should be understood by those skilled in the art to which the embodiments of the present invention pertain.

It should be understood that portions of the invention may be implemented in hardware, software, firmware or a combination thereof. In the above-described embodiments, multiple steps or methods may be implemented in software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented by any one or combination of the following techniques well known in the art: having logic gates for implementing logic functions on data signals. Discrete logic circuits, application specific integrated circuits with suitable combinational logic gates, programmable gate arrays (PGAs), field programmable gate arrays (FPGAs), etc.

One of ordinary skill in the art can understand that all or part of the steps carried by the method of implementing the above embodiments can be completed by a program to instruct related hardware, and the program can be stored in a computer readable storage medium. When executed, one or a combination of the steps of the method embodiments is included.

Embodiments of the present invention also provide a storage medium. Optionally, in the embodiment, the foregoing storage medium may be configured to store program code for performing the following steps:

S1, when determining that the SD card to be read and written is a preset SD card, determining whether the device inserted into the SD card is to write the data in the memory to at least one preset SD card before accessing the SD card to be read or written. in;

S2, if the data is written into at least one preset SD card, at least one preset SD card is used as the target SD card;

S3, determining whether the SD card to be read or written is a target SD card;

S4, if the SD card to be read or written is the target SD card, save the data that has been written in the SD card to be read and written, and write the data that has not been written in the memory of the device into the first directory in the SD card to be read and written. under.

Optionally, in this embodiment, the foregoing storage medium may include, but is not limited to: a USB flash drive, only A medium that can store program code, such as a read-only memory (ROM), a random access memory (RAM), a removable hard disk, a magnetic disk, or an optical disk.

In addition, each functional unit in each embodiment of the present invention may be integrated into one processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above integrated modules can be implemented in the form of hardware or in the form of software functional modules. The integrated modules, if implemented in the form of software functional modules and sold or used as stand-alone products, may also be stored in a computer readable storage medium.

The above mentioned storage medium may be a read only memory, a magnetic disk or an optical disk or the like.

In the description of the present specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" and the like means a specific feature described in connection with the embodiment or example. A structure, material or feature is included in at least one embodiment or example of the invention. In the present specification, the schematic representation of the above terms does not necessarily mean the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples.

Although the embodiments of the present invention have been shown and described, it is understood that the above-described embodiments are illustrative and are not to be construed as limiting the scope of the invention. The embodiments are subject to variations, modifications, substitutions and variations.

Industrial applicability

In the embodiment of the present invention, data that has not been written in the memory of the device can be written into the SD card that is removed before being inserted again, thereby improving data reading and writing accuracy, avoiding data loss, and effectively improving the user experience.

Claims

A method for reading and writing an SD card, comprising the following steps:

When it is determined that the SD card to be read and written is a preset SD card, it is determined whether the device inserted in the SD card to be read and written writes at least one preset data in the memory before accessing the SD card to be read or written. In the SD card;

If the data is written into the at least one preset SD card, the at least one preset SD card is used as the target SD card;

Determining whether the SD card to be read or written is the target SD card;

If the SD card to be read and written is the target SD card, save the data that has been written in the SD card to be read and written, and write data that has not been written in the memory of the device to the to-be-read Write the first directory in the SD card.
The method for reading and writing an SD card according to claim 1, further comprising:

Detecting whether the SD card to be read and written is removed from the device;

If the SD card to be read or written is not removed from the device, when the data is written, the second directory in the device is uninstalled, wherein the second directory is to write the data. a storage directory of the data in the memory of the device before the SD card to be read or written;

Changing a path in the device that locates the second directory to a path that locates the first directory.
The method for reading and writing an SD card according to claim 2, wherein the detecting whether the SD card to be read or written is removed from the device further comprises:

If the SD card to be read and written is removed from the device, it is determined whether the data in the memory has been written into the SD card to be read and written before the SD card to be read or written is removed;

If the data in the memory has been written to the SD card to be read and written, the second directory is mounted, and the path of the first directory in the device is changed to the positioning The path to the second directory.
The method for reading and writing an SD card according to claim 1, wherein the SD card to be read and written is determined to be the preset SD card by the following steps:

Obtaining a preset identifier of the SD card to be read and written;

Detecting whether the preset identifier has a record in the inserted device;

If the preset identifier has the record in the inserted device, determining that the SD card to be read and written is the preset SD card.
The method for reading and writing an SD card according to claim 4, wherein the detecting whether the preset identifier has a record in the inserted device further comprises:

If the preset identifier does not exist in the inserted device, the SD card to be read and written is formatted.
A reading and writing device for an SD card, comprising:

The first determining module is configured to determine, when determining that the SD card to be read or written is a preset SD card, whether the device inserted in the SD card to be read and written writes data in the memory before accessing the SD card to be read or written Enter at least one preset SD card;

The first processing module is configured to: when the data is written into the at least one preset SD card, use the at least one preset SD card as a target SD card;

a second determining module, configured to determine whether the SD card to be read or written is the target SD card;

Saving a module, when the SD card to be read and written is the target SD card, And storing the data that has been written in the SD card to be read and written, and writing data that has not been written in the memory of the device to the first directory in the SD card to be read and written.
The apparatus for reading and writing of an SD card according to claim 6, further comprising:

a first detecting module, configured to detect whether the SD card to be read and written is removed from the device;

And the uninstalling module is configured to: when the SD card to be read or written is not removed from the device, uninstall the second directory in the device when the data is written, wherein the second directory is a storage directory of the data in the memory of the device before the data is written to the SD card to be read or written;

And a change module configured to change a path in the device that locates the second directory to a path that locates the first directory.
The apparatus for reading and writing of an SD card according to claim 7, further comprising:

a third determining module, configured to: when the SD card to be read and written is removed from the device, determine whether data in the memory has been written into the to-be-read before reading and writing the SD card to be read or written SD card;

a mounting module, configured to: when the data in the memory has been written into the SD card to be read and written, mount the second directory, and change a path in the device that locates the first directory to The path of the second directory is located.
The method for reading and writing an SD card according to claim 6, wherein whether the SD card to be read or written is the preset SD card is determined by the following module:

Obtaining a module, configured to obtain a preset identifier of the SD card to be read and written;

a second detecting module, configured to detect whether the preset identifier has a record in the inserted device;

The second processing module is configured to determine that the SD card to be read and written is the preset SD card when the preset identifier exists in the inserted device.
The apparatus for reading and writing of an SD card according to claim 9, wherein the second processing module is further configured to:

When the preset identifier does not exist in the inserted device, the SD card to be read and written is formatted.