从 url 获取数据时出现问题

这是我写的代码

NSString *str = [NSString stringWithFormat:@"https://graph.facebook.com/me?access_token=CAADbwxRRgq8BANULcGGn3d4NPZB4LlP3tCL9YjYH3Nd0fD2XvgjG0qTECEmOsFhNhcu4NCdgYzQK3lYaATiedLRP4ZAIRgf8FBtDBYd22z5BrMabHlex12nZAbm8UfJTrPVRw5rjN8abi9"];


NSURL* url = [NSURL URLWithString:[str stringByReplacingPercentEscapesUsingEncoding:NSUTF8StringEncoding]];

NSError* error = nil;
NSData* data = [NSData dataWithContentsOfURL:url options:NSDataReadingUncached error:&error];
if (error) {
     NSLog(@"%@", [error localizedDescription]);
} else {
     NSLog(@"Data has loaded successfully.");
}

我收到错误

错误域 = NSCocoaErrorDomain 代码 = 256 “该操作无法 完全的。 （可可错误 256。）” UserInfo=0x218446a0

{NSURL=https://graph.facebook.com/me?access_token=CAADbwxRRgq8BANULcGGn3d4NPZB4LlP3tCL9YjYH3Nd0fD2XvgjG0qTECEmOsFhNhcu4NCdgYzQK3lYaATiedLRP4ZAIRgf8FBtDBYd22z5BrMabHlex12nZAbm8UfJTrPVRw5rjN8abi9ZBoVD1DYVZCo8hcZC0n2CnMyk3ryeCQntRpdZCc2e}

Try:

NSString *str = [NSString stringWithFormat:@"https://graph.facebook.com/me?access_token=CAADbwxRRgq8BANULcGGn3d4NPZB4LlP3tCL9YjYH3Nd0fD2XvgjG0qTECEmOsFhNhcu4NCdgYzQK3lYaATiedLRP4ZAIRgf8FBtDBYd22z5BrMabHlex12nZAbm8UfJTrPVRw5rjN8abi9"];


NSURL* url = [NSURL URLWithString:[str stringByReplacingPercentEscapesUsingEncoding:NSUTF8StringEncoding]];

NSError* error = nil;
NSData* data = [NSURLConnection sendSynchronousRequest:[NSURLRequest requestWithURL:url cachePolicy:NSURLRequestReloadIgnoringCacheData timeoutInterval:30] returningResponse:nil error:&error];

if (error) {
    NSLog(@"%@", [error localizedDescription]);
} else {
    NSLog(@"Data has loaded successfully.");
}

不过，我不知道为什么你的其他请求失败。错误代码 256 的描述性并不强。