android读取sd卡上文件中的数据

从sd卡上的文件中读取数据

第1种方法：

public static String readFileMsg(String filePath) {
        if (TextUtils.isEmpty(filePath)) {
            return "";
        }
        BufferedReader reader = null;
        try {
            File file = new File(filePath);
            if (!file.exists()) {
                return "";
            }
            reader = new BufferedReader(new FileReader(file));
            String line;
            StringBuilder content = new StringBuilder();
            while((line = reader.readLine()) != null) {
                content.append(line);
            }
            return content.toString();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (reader != null) {
                try {
                    reader.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return "";
    }

第2种方法：

public static String readFileMsg(String filePath) {
InputStream inStream = null;
BufferedReader reader = null;
try {
    StringBuilder content = new StringBuilder();
    File file = new File(filePath);
    if (!file.exists()) {
        return "";
    }
    inStream = new FileInputStream(file);
    if (inStream != null) {
        InputStreamReader inputReader = new InputStreamReader(inStream);
        reader = new BufferedReader(inputReader);
        String line;
        while ((line = reader.readLine()) != null) {
            content.append(line);
        }
        reader.close();
        return content.toString();
    }
} catch (Exception e) {
    e.printStackTrace();
} finally {
    if(inStream != null) {
        try {
            inStream.close();
        } catch(IOException e) {
            
        }
    }
}
return "";
}