我与Android平台是一个新手。 一个文件中的位置已经创建的data/data/myapp/files/hello.txt ; 这个文件的内容是“你好”。 如何读取文件的内容？
Answer 1:
看看这个如何在Android上使用储存http://developer.android.com/guide/topics/data/data-storage.html#filesInternal
要读取内部存储的数据，你需要你的应用程序文件的文件夹，并从这里阅读内容
String yourFilePath = context.getFilesDir() + "/" + "hello.txt";
File yourFile = new File( yourFilePath );
你也可以使用这种方法
FileInputStream fis = context.openFileInput("hello.txt");
InputStreamReader isr = new InputStreamReader(fis);
BufferedReader bufferedReader = new BufferedReader(isr);
StringBuilder sb = new StringBuilder();
String line;
while ((line = bufferedReader.readLine()) != null) {
sb.append(line);
}
Answer 2:
读取文件作为字符串完整版（处理异常，使用UTF-8，处理新线）：
// Calling:
/*
Context context = getApplicationContext();
String filename = "log.txt";
String str = read_file(context, filename);
*/
public String read_file(Context context, String filename) {
try {
FileInputStream fis = context.openFileInput(filename);
InputStreamReader isr = new InputStreamReader(fis, "UTF-8");
BufferedReader bufferedReader = new BufferedReader(isr);
StringBuilder sb = new StringBuilder();
String line;
while ((line = bufferedReader.readLine()) != null) {
sb.append(line).append("\n");
}
return sb.toString();
} catch (FileNotFoundException e) {
return "";
} catch (UnsupportedEncodingException e) {
return "";
} catch (IOException e) {
return "";
}
}
注意：您不必只与文件名操心文件的路径。
Answer 3:
调用以下函数的参数，你的文件路径：
private String getFileContent(String targetFilePath){
File file = new File(targetFilePath);
try {
fileInputStream = new FileInputStream(file);
}
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
Log.e("",""+e.printStackTrace());
}
StringBuilder sb;
while(fileInputStream.available() > 0) {
if(null== sb) sb = new StringBuilder();
sb.append((char)fileInputStream.read());
}
String fileContent;
if(null!=sb){
fileContent= sb.toString();
// This is your fileContent in String.
}
try {
fileInputStream.close();
}
catch(Exception e){
// TODO Auto-generated catch block
Log.e("",""+e.printStackTrace());
}
return fileContent;
}
Answer 4:
String path = Environment.getExternalStorageDirectory().toString();
Log.d("Files", "Path: " + path);
File f = new File(path);
File file[] = f.listFiles();
Log.d("Files", "Size: " + file.length);
for (int i = 0; i < file.length; i++) {
//here populate your listview
Log.d("Files", "FileName:" + file[i].getName());
}
Answer 5:
要读取内部存储的文件中：
呼叫openFileInput（），并通过它来读取文件的名称。 这将返回一个FileInputStream。 读取从文件中读取的字节（）。 然后关闭关闭流（）。
码：：
StringBuilder sb = new StringBuilder();
try{
BufferedReader reader = new BufferedReader(new InputStreamReader(is, "UTF-8"));
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line).append("\n");
}
is.close();
} catch(OutOfMemoryError om){
om.printStackTrace();
} catch(Exception ex){
ex.printStackTrace();
}
String result = sb.toString();
Answer 6:
我更喜欢使用java.util.Scanner ：
try {
Scanner scanner = new Scanner(context.openFileInput(filename)).useDelimiter("\\Z");
StringBuilder sb = new StringBuilder();
while (scanner.hasNext()) {
sb.append(scanner.next());
}
scanner.close();
String result = sb.toString();
} catch (IOException e) {}
Answer 7:
对于其他人寻找一个答案，为什么一个文件不是可读尤其是在SD卡，写这样的文件第一次..注意MODE_WORLD_READABLE
try {
FileOutputStream fos = Main.this.openFileOutput("exported_data.csv", MODE_WORLD_READABLE);
fos.write(csv.getBytes());
fos.close();
File file = Main.this.getFileStreamPath("exported_data.csv");
return file.getAbsolutePath();
} catch (Exception e) {
e.printStackTrace();
return null;
}
文章来源: How do I read the file content from the Internal storage - Android App
