ios 把NSMutableArray 写入.plist 文件中

NSArray *path = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    //获取document 路径
    NSLog(@"%@",path[0]);

    //获取完整路径
    NSString *documentsPath = [path objectAtIndex:0];
    NSString *plistPath = [documentsPath stringByAppendingPathComponent:@"MY_PropertyList.plist"];

    NSMutableDictionary *usersDic = [[NSMutableDictionary alloc ] init];
    //设置属性值
    [usersDic setObject:@"孙悟空" forKey:@"name"];
    [usersDic setObject:@"sunwukong" forKey:@"password"];

    NSMutableDictionary *usersDic1 = [[NSMutableDictionary alloc ] init];
    //设置属性值
    [usersDic1 setObject:@"孙悟空" forKey:@"name"];
    [usersDic1 setObject:@"sunwukong" forKey:@"password"];
    NSMutableArray *arr1 = [[NSMutableArray alloc] init];

    [arr1 addObject:usersDic];

    [arr1 addObject:usersDic1];
    //写入文件
    [arr1 writeToFile:plistPath atomically:YES];