如何在ENOENT IOexception中保存文件

user1796624 发表于 Dev

用户名

如何在Android中保存文件？我有以下代码：

 final File file = new File(cont.getExternalFilesDir(null), filename);
                if (!file.exists()) {
                    file.createNewFile();
                }

我得到

03-21 11:31:29.903: W/System.err(31668): java.io.IOException: open failed: ENOENT (No such file or directory)
03-21 11:31:29.903: W/System.err(31668):    at java.io.File.createNewFile(File.java:948)

我保存文件的完整代码如下：

final File file = new File(context.getExternalFilesDir(null), filename);
            if (!file.exists()) {
                // file.mkdirs();
                file.createNewFile();
            }
            final OutputStream output = new FileOutputStream(file);
            try {
                try {
                    final byte[] buffer = new byte[1024];
                    int read;
                    while ((read = input.read(buffer)) != -1)
                        output.write(buffer, 0, read);
                    output.flush();
                } finally {
                    output.close();
                }
                Log.i("save_file", "save to disk is ok");
            } catch (Exception e) {
                e.printStackTrace();
            }

我也有权限：

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

有人可以指出我做错了吗，谢谢

编辑：问题是我想要保存的文件的名称，所以它不应该包含受限的字符，我的格式是这样的："xxx/xxx.jpg"因此'/'不是文件名的有效字符。谢谢

用户名

最好使用Environment.getExternalStorageDirectory（）而不是context.getExternalFilesDir（null），即使看起来相同。

这是我的代码：

String extr = Environment.getExternalStorageDirectory().toString();
        File mFolder = new File(extr + "/MainFolder_Photo");

        if (!mFolder.exists()) {
            mFolder.mkdir();
        }

        String strF = mFolder.getAbsolutePath();
        mSubFolder = new File(strF + "/Pictures");

        if (!mSubFolder.exists()) {
            mSubFolder.mkdir();
        } 

        // check file are there or not;// if present delete

        try {


        File yourDir = new File(mSubFolder.getAbsoluteFile().toString());
        for (File f : yourDir.listFiles()) {

            if (f.length()>0){

        f.delete();

            }

        }
        } catch (Exception e) {
            // TODO: handle exception
        }
        // file name
        String s = "Puzzle_Photo.png";

        File f = new File(mSubFolder.getAbsolutePath(), s);

        strMyImagePath = f.getAbsolutePath();

        OutputStream output;
        try {
            output = new FileOutputStream(f);
            URL url = new URL("file://" + filePath);// your data
            InputStream input = url.openStream();
            byte[] buffer = new byte[1024];
            int bytesRead = 0;
            while ((bytesRead = input.read(buffer, 0, buffer.length)) >= 0) {
                output.write(buffer, 0, bytesRead);
            }

            output.close();
            input.close();

            return true;

        } catch (Exception e) {

            e.printStackTrace();
        }