plist文件读写

[cpp] - (void)viewDidLoad
{
[super viewDidLoad];

NSDictionary *dictionary1 = [NSDictionary dictionaryWithObjectsAndKeys:@"1",@"a",@"2",@"b", nil];
NSDictionary *dictionary2 = [NSDictionary dictionaryWithObjectsAndKeys:@"3",@"c",@"4",@"d", nil];

// 获取应用程序沙盒的Documents目录
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask,YES);
NSString *plistPath = [paths objectAtIndex:0];

// plist文件完整路径
NSString *filename=[plistPath stringByAppendingPathComponent:@"test.plist"];

// *写入(原有数据被覆盖)
[dictionary1 writeToFile:filename atomically:YES];
[dictionary2 writeToFile:filename atomically:YES];

// *读取
NSDictionary *dic = [[NSMutableDictionary alloc] initWithContentsOfFile:filename];
NSLog(@"%@", dic);
}

- (void)viewDidLoad
{
[super viewDidLoad];

NSDictionary *dictionary1 = [NSDictionary dictionaryWithObjectsAndKeys:@"1",@"a",@"2",@"b", nil];
NSDictionary *dictionary2 = [NSDictionary dictionaryWithObjectsAndKeys:@"3",@"c",@"4",@"d", nil];

// 获取应用程序沙盒的Documents目录
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask,YES);
NSString *plistPath = [paths objectAtIndex:0];

// plist文件完整路径
NSString *filename=[plistPath stringByAppendingPathComponent:@"test.plist"];

// *写入(原有数据被覆盖)
[dictionary1 writeToFile:filename atomically:YES];
[dictionary2 writeToFile:filename atomically:YES];

// *读取
NSDictionary *dic = [[NSMutableDictionary alloc] initWithContentsOfFile:filename];
NSLog(@"%@", dic);
}

结论:重复对同一plist写入数据，后一次写入的数据将覆盖前一次写入的数据。