android，如何重命名文件？

android, How to rename a file?

提问by Hesam

In my application, I need to record video. Before start of recording in I'm assigning a name and directory to it. After recording is finished user has ability to rename his file. I wrote following code but seem it doesn't work.

在我的应用程序中，我需要录制视频。在开始录制之前，我正在为其分配一个名称和目录。录制完成后，用户可以重命名他的文件。我写了以下代码，但似乎不起作用。

When user enters name of file and click on button I'll do this:

当用户输入文件名并单击按钮时，我将执行以下操作：

private void setFileName(String text) {     
        String currentFileName = videoURI.substring(videoURI.lastIndexOf("/"), videoURI.length());
        currentFileName = currentFileName.substring(1);
        Log.i("Current file name", currentFileName);

        File directory = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_MOVIES), MEDIA_NAME);
        File from      = new File(directory, "currentFileName");
        File to        = new File(directory, text.trim() + ".mp4");
        from.renameTo(to);
        Log.i("Directory is", directory.toString());
        Log.i("Default path is", videoURI.toString());
        Log.i("From path is", from.toString());
        Log.i("To path is", to.toString());
    }

Text: is the name which is entered by user. Current Filename: is the name which is assigned by me before recording MEDIA_NAME: name of folder

文本：是用户输入的名称。当前文件名：是我在录制前分配的名称 MEDIA_NAME：文件夹名称

Logcat shows this:

Logcat 显示了这一点：

05-03 11:56:37.295: I/Current file name(12866): Mania-Karaoke_20120503_115528.mp4
05-03 11:56:37.295: I/Directory is(12866): /mnt/sdcard/Movies/Mania-Karaoke
05-03 11:56:37.295: I/Default path is(12866): /mnt/sdcard/Movies/Mania-Karaoke/Mania-Karaoke_20120503_115528.mp4
05-03 11:56:37.295: I/From path is(12866): /mnt/sdcard/Movies/Mania-Karaoke/currentFileName
05-03 11:56:37.295: I/To path is(12866): /mnt/sdcard/Movies/Mania-Karaoke/hesam.mp4

Any suggestion would be appreciated.

任何建议将不胜感激。

采纳答案by COD3BOY

The problem is in this line,

问题出在这一行，

File from = new File(directory, "currentFileName");

Here currentFileNameis actually a String you dont have to use "

这currentFileName实际上是一个你不必使用的字符串"

try it this way,

试试这个方法

File from      = new File(directory, currentFileName  );
                                    ^               ^         //You dont need quotes

回答by Niranjan

In your code:

在您的代码中：

Shouldn't it be :

不应该是：

File from = new File(directory, currentFileName);

File from = new File(directory, currentFileName);

instead of

代替

File from = new File(directory, "currentFileName");

File from = new File(directory, "currentFileName");

---

---

For safety,

为了安全，

Use the File.renameTo() . But check for directory existence before renaming it!

使用 File.renameTo() 。但是在重命名之前检查目录是否存在！

File dir = Environment.getExternalStorageDirectory();
if(dir.exists()){
    File from = new File(dir,"from.mp4");
    File to = new File(dir,"to.mp4");
     if(from.exists())
        from.renameTo(to);
}

Refer: http://developer.android.com/reference/java/io/File.html#renameTo%28java.io.File%29

参考：http: //developer.android.com/reference/java/io/File.html#renameTo%28java.io.File%29

回答by Thomas Vos

Use this method to rename a file. The file fromwill be renamed to to.

使用此方法重命名文件。该文件from将重命名为to.

private boolean rename(File from, File to) {
    return from.getParentFile().exists() && from.exists() && from.renameTo(to);
}

Example code:

示例代码：

public class MainActivity extends Activity {
    private static final String TAG = "YOUR_TAG";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        File currentFile = new File("/sdcard/currentFile.txt");
        File newFile = new File("/sdcard/newFile.txt");

        if (rename(currentFile, newFile)) {
            //Success
            Log.i(TAG, "Success");
        } else {
            //Fail
            Log.i(TAG, "Fail");
        }
    }

    private boolean rename(File from, File to) {
        return from.getParentFile().exists() && from.exists() && from.renameTo(to);
    }
}

回答by taran mahal

/**
 * ReName any file
 * @param oldName
 * @param newName
 */
public static void renameFile(String oldName,String newName){
    File dir = Environment.getExternalStorageDirectory();
    if(dir.exists()){
        File from = new File(dir,oldName);
        File to = new File(dir,newName);
         if(from.exists())
            from.renameTo(to);
    }
}

回答by Jawad Zeb

Working example...

工作示例...

   File oldFile = new File("your old file name");
    File latestname = new File("your new file name");
    boolean success = oldFile .renameTo(latestname );

   if(success)
    System.out.println("file is renamed..");

回答by Krishnakant Dalal

Provide target File object with different file Name.

提供具有不同文件名的目标文件对象。

// Copy the source file to target file.
// In case the dst file does not exist, it is created
void copy(File source, File target) throws IOException {

    InputStream in = new FileInputStream(source);
    OutputStream out = new FileOutputStream(target);

    // Copy the bits from instream to outstream
    byte[] buf = new byte[1024];
    int len;

    while ((len = in.read(buf)) > 0) {
        out.write(buf, 0, len);
    }

    in.close();
    out.close();
}

回答by Changwei Yao

you should check if the directory exist!

你应该检查目录是否存在！

File directory = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_MOVIES), MEDIA_NAME);
if(!directory.exist()){
    directory.mkdirs();
}

回答by Jon

This is what I ended up using. It handles the case where there is an existing file with the same name by adding an integer to the file name.

这就是我最终使用的。它通过向文件名添加整数来处理存在同名文件的情况。

@NonNull
private static File renameFile(@NonNull File from, 
                               @NonNull String toPrefix, 
                               @NonNull String toSuffix) {
    File directory = from.getParentFile();
    if (!directory.exists()) {
        if (directory.mkdir()) {
            Log.v(LOG_TAG, "Created directory " + directory.getAbsolutePath());
        }
    }
    File newFile = new File(directory, toPrefix + toSuffix);
    for (int i = 1; newFile.exists() && i < Integer.MAX_VALUE; i++) {
        newFile = new File(directory, toPrefix + '(' + i + ')' + toSuffix);
    }
    if (!from.renameTo(newFile)) {
        Log.w(LOG_TAG, "Couldn't rename file to " + newFile.getAbsolutePath());
        return from;
    }
    return newFile;
}

回答by twenk11k

    public void renameFile(File file,String suffix) {

    String ext = FilenameUtils.getExtension(file.getAbsolutePath());
    File dir = file.getParentFile();

    if(dir.exists()){
        File from = new File(dir,file.getName());
        String name = file.getName();
        int pos = name.lastIndexOf(".");
        if (pos > 0) {
            name = name.substring(0, pos);
        }
        File to = new File(dir,name+suffix+"."+ext);
        if(from.exists())
           from.renameTo(to);
    }

}