WP7 isolated storage series-2. Create folders and files

This is the second short article on the series "WP7 isolated storage series", focusing on real and practical examples with source code, rather than the theory of inventory. Next I will discuss how to create folders and files in Windows Phone 7 isolated storage.

·
WP7 isolated storage series-1. Introduction to isolated storage

·
WP7 isolated storage series-2. Create folders and files

·
WP7 isolated storage series-3. Use isolatedstoragesettings to store data

·
WP7 isolated storage series-4. Read and store text files

·
WP7 isolated storage series-5. Use xmlserializer to read and store XML files

·
WP7 isolated storage series-6. Use xmlwriter to read and store XML files

·
WP7 isolated storage series-7. Reading and storing images

·
WP7 isolated storage series-8. Read and store captured images

·
WP7 isolated storage series-9. Read and store binary files

·
WP7 isolated storage series-10. File Operations

·
WP7 isolated storage series-11. Suggestions and best practices

·
WP7 isolated storage series-12. open source database and help library files

Let's start by creating a simple Windows Phone 7 project. Next, add the following namespaces to mainpage. XAML. CS (or you can use this code on another page ):

using System.IO;using System.IO.IsolatedStorage;

Folder in WP7 isolated storage

·Create a folder

To create a folder named "new folder", we only need to call the createdirectory method of isolatedstoragefile:

IsolatedStorageFile myIsolatedStorage = IsolatedStorageFile.GetUserStoreForApplication(); myIsolatedStorage.CreateDirectory("NewFolder");

Note: You can also create a compositing path folder other than "new folder", such as "folder1/folder2/folder3/newfolder ".

myIsolatedStorage.CreateDirectory("Folder1/Folder2/Folder3/NewFolder");

·Delete folder

To delete a folder, you only need to call the isolatedstoragefile method deletedirectory:

myIsolatedStorage.DeleteDirectory("NewFolder");

·Best practices

-Always check whether this directory exists

myIsolatedStorage.DirectoryExists(directoryName)

-When using isolated storage, try {} catch {} is always used to prevent users from seeing unexpected exceptions. The following method creates a folder using the parameter folder Name:

public void CreateDirectory(string directoryName){try{IsolatedStorageFile myIsolatedStorage = IsolatedStorageFile.GetUserStoreForApplication();if(!string.IsNullOrEmpty(directoryName) && !myIsolatedStorage.DirectoryExists(directoryName)){myIsolatedStorage.CreateDirectory(directoryName);}}catch (Exception ex){// handle the exception}}

To create a folder, you only need to call this method and assign the required parameters:

this.CreateDirectory("NewFolder");

-You can also use the same check to delete folders:

Note: The folder must be empty before it is deleted. Once deleted, the folder cannot be restored.

public void DeleteDirectory(string directoryName){try{IsolatedStorageFile myIsolatedStorage = IsolatedStorageFile.GetUserStoreForApplication();if (!string.IsNullOrEmpty(directoryName) && myIsolatedStorage.DirectoryExists(directoryName)){myIsolatedStorage.DeleteDirectory(directoryName);}}catch (Exception ex){// handle the exception}}

To delete a folder, you only need to call this method:

this.DeleteDirectory("NewFolder");

Note: Currently, an isolated storage cannot be used to rename a folder.

Files in WP7 isolated storage

·Create a file

To create a file named “somefile.txt, you only need to use streamwriter:

IsolatedStorageFile myIsolatedStorage = IsolatedStorageFile.GetUserStoreForApplication();StreamWriter writeFile = new StreamWriter(new IsolatedStorageFileStream("NewFolder\\SomeFile.txt", FileMode.CreateNew, myIsolatedStorage));

Note: If you do not specify any folder, the file will be created under the root directory. You can also use isolatedstoragefilestream to create files:

IsolatedStorageFileStream stream1 = new IsolatedStorageFileStream("SomeTextFile.txt", FileMode.Create, myIsolatedStorage);

·Delete an object

To delete a file from isolated storage, you only need to call the deletefile method of isolatedstoragefile:

myIsolatedStorage.DeleteFile("NewFolder/SomeFile.txt");

·Best practices

-Always check whether the folder where the file to be created exists

myIsolatedStorage.DirectoryExists(directoryName)

-Always check whether the file we are about to create exists. If yes, you must Delete the existing file and create a new one.

myIsolatedStorage.FileExists(filePath)

-When using isolated storage, try {} catch {} is always used to prevent users from seeing unexpected exceptions. The following method creates a folder using the parameter folder Name:

try{IsolatedStorageFile myIsolatedStorage = IsolatedStorageFile.GetUserStoreForApplication();StreamWriter writeFile;if (!myIsolatedStorage.DirectoryExists("NewFolder")){myIsolatedStorage.CreateDirectory("NewFolder");writeFile = new StreamWriter(new IsolatedStorageFileStream("NewFolder\\SomeFile.txt", FileMode.CreateNew, myIsolatedStorage));}else{writeFile = new StreamWriter(new IsolatedStorageFileStream("NewFolder\\SomeFile.txt", FileMode.CreateNew, myIsolatedStorage));}}catch (Exception ex){// do something with exception}

Note: to completely delete all data in isolated storage, you only need to call store. Remove (). Here, "Store" is an instance of isolatedstoragefile.

In this article, I discussed how to create folders and files in WP7 isolated storage. We look forward to the following articles.

 

Link: http://www.windowsphonegeek.com/tips/all-about-wp7-isolated-storage-files-and-folders