android中Assets目录中资源的使用方法例子

private void copyFile() {
AssetManager manager = getAssets();
try {
InputStream in = manager.open("commonnum.db");
File file = new File("/sdcard/commonnum.db");
FileOutputStream fos = new FileOutputStream(file);
byte[] buffer = new byte[1024];
int len = 0;
while(-1 != (len = in.read(buffer))){
fos.write(buffer, 0, len);
}
fos.flush();
fos.close();
in.close();

} catch (IOException e) {
Toast.makeText(this, "常用号码文件不存在", 0).show();
}
}

File file = new File("/sdcard/commonnum.db");
if (!file.exists()) {
copyFile();
}