Question

我可以将前缀点（“。”）成功应用于所有.gif扩展名的文件。例如，将“my_file.gif”重命名为“.my_file.gif”。但是，我想使用代码再次删除此前缀点（AKA反向）。我试过了，但是不行。（根本不删除点）下面是我的代码和我的方法 -

这是添加点前缀的代码（工作正常） -

    // getting SDcard root path
    File dir = new File(Environment.getExternalStorageDirectory()
            .getAbsolutePath());
    walkdir(dir);
}
//detect files having these extensions and rename them
public static final String[] TARGET_EXTENSIONS = { "gif"};
public void walkdir(File dir) { 
    File listFile[] = dir.listFiles();
    if (listFile != null) {
        for (int i = 0; i < listFile.length; i++) {
            if (listFile[i].isDirectory()) {
                walkdir(listFile[i]);
            } else {
                String fPath = listFile[i].getPath();
                for (String ext : TARGET_EXTENSIONS) {
                    if (fPath.endsWith(ext)) {
                        putDotBeforeFileName(listFile[i]);
                    }
                }
            }
        }
    }
}

private String putDotBeforeFileName(File file) {
    String fileName = file.getName();
    String fullPath = file.getAbsolutePath();
    int indexOfFileNameStart = fullPath.lastIndexOf(fileName);
    StringBuilder sb = new StringBuilder(fullPath);
    sb.insert(indexOfFileNameStart, ".");
    String myRequiredFileName = sb.toString();
    file.renameTo(new File(myRequiredFileName));
    return myRequiredFileName;
  }
}

这是我删除不起作用的点前缀的方法（没有强制关闭） -

private String putDotBeforeFileName(File file) {
    String fileName = file.getName();
    String fullPath = file.getAbsolutePath();
    int indexOfDot = fullPath.indexOf(".");
    String myRequiredFileName = "";
    if (indexOfDot == 0 && fileName.length() > 1) {
        myRequiredFileName = file.getParent() + "/" + fileName.substring(1);
    }
    try {
        Runtime.getRuntime().exec(
                "mv " + file.getAbsolutePath() + " " + myRequiredFileName);
    } catch (IOException e) {
        e.printStackTrace();
    }
    return myRequiredFileName;
}

Answer 1

试试此代码

private String removeDotBeforeFileName(File file) {
        String fileName = file.getName();
        String fullPath = file.getAbsolutePath();
        String myRequiredFileName = "";
        if (fileName.length() > 1 && fullPath.charAt(0)=='.') {
            myRequiredFileName = file.getParent() + "/" + fileName.substring(1);
           file.renameTo(new File(myRequiredFileName));
        }

        return myRequiredFileName;
    }

如何在android中重命名文件？

1 个答案: