Android读写文件
一、 从resource中的raw文件夹中获取文件并读取数据(资源文件只能读不能写)
String res = "";
try{
InputStream in = getResources().openRawResource(R.raw.bbi);
//在\Test\res\raw\bbi.txt,
int length = in.available();
byte [] buffer = new byte[length];
in.read(buffer);
//res = EncodingUtils.getString(buffer, "UTF-8");
//res = EncodingUtils.getString(buffer, "UNICODE");
res = EncodingUtils.getString(buffer, "BIG5");
//依bbi.txt的编码类型选择合适的编码,如果不调整会乱码
in.close();
}catch(Exception e){
e.printStackTrace();
}
myTextView.setText(res);//把得到的内容显示在TextView上
二、 从asset中获取文件并读取数据(资源文件只能读不能写)
String fileName = "yan.txt"; //文件名字
String res="";
try{
InputStream in = getResources().getAssets().open(fileName);
// \Test\assets\yan.txt这里有这样的文件存在
int length = in.available();
byte [] buffer = new byte[length];
in.read(buffer);
res = EncodingUtils.getString(buffer, "UTF-8");
}catch(Exception e){
e.printStackTrace();
}
三、 从sdcard中去读文件,首先要把文件通过\android-sdk-windows\tools\adb.exe把本地计算机上的文件copy到sdcard上去,adb.exe push e:/Y.txt /sdcard/, 不可以用adb.exe push e:\Y.txt \sdcard\同样: 把仿真器上的文件copy到本地计算机上用: adb pull ./data/data/com.tt/files/Test.txt e:/
String fileName = "/sdcard/Y.txt";
//也可以用String fileName = "mnt/sdcard/Y.txt";
String res="";
try{
FileInputStream fin = new FileInputStream(fileName);
//FileInputStream fin = openFileInput(fileName);
//用这个就不行了,必须用FileInputStream
int length = fin.available();
byte [] buffer = new byte[length];
fin.read(buffer);
res = EncodingUtils.getString(buffer, "UTF-8");
fin.close();
}catch(Exception e){
e.printStackTrace();
}
myTextView.setText(res);
四、 写文件, 一般写在\data\data\com.test\files\里面,打开DDMS查看file explorer是可以看到仿真器文件存放目录的结构的
String fileName = "TEST.txt";
String message = "FFFFFFF11111FFFFF" ;
writeFileData(fileName, message);
public voidwriteFileData(String fileName,String message){
try{
FileOutputStream fout =openFileOutput(fileName, MODE_PRIVATE);
byte [] bytes = message.getBytes();
fout.write(bytes);
fout.close();
}
catch(Exception e){
e.printStackTrace();
}
}
五、 写, 读data/data/目录(相当AP工作目录)上的文件,用openFileOutput
//写文件在./data/data/com.tt/files/下面
public voidwriteFileData(String fileName,String message){
try{
FileOutputStream fout =openFileOutput(fileName, MODE_PRIVATE);
byte [] bytes = message.getBytes();
fout.write(bytes);
fout.close();
}
catch(Exception e){
e.printStackTrace();
}
}
//-------------------------------------------------------
//读文件在./data/data/com.tt/files/下面
public String readFileData(String fileName){
String res="";
try{
FileInputStream fin = openFileInput(fileName);
int length = fin.available();
byte [] buffer = new byte[length];
fin.read(buffer);
res = EncodingUtils.getString(buffer, "UTF-8");
fin.close();
}
catch(Exception e){
e.printStackTrace();
}
return res;
}
六、 写, 读sdcard目录上的文件,要用FileOutputStream, 不能用openFileOutput
//写在/mnt/sdcard/目录下面的文件
public voidwriteFileSdcard(String fileName,String message){
try{
//FileOutputStream fout = openFileOutput(fileName, MODE_PRIVATE);
FileOutputStream fout = newFileOutputStream(fileName);
byte [] bytes = message.getBytes();
fout.write(bytes);
fout.close();
}
catch(Exception e){
e.printStackTrace();
}
}
//读在/mnt/sdcard/目录下面的文件
public String readFileSdcard(String fileName){
String res="";
try{
FileInputStream fin = new FileInputStream(fileName);
int length = fin.available();
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补充:移动开发 , Android ,