json 将 NSString 转换为 NSData - [NSString dataUsingEncoding] 异常
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converting NSString to NSData - [NSString dataUsingEncoding] exception
提问by Fury
I was converting NSString to NSData in order to parse by JSON, but I got the following error.
我正在将 NSString 转换为 NSData 以便通过 JSON 进行解析，但出现以下错误。
Terminating app due to uncaught exception 'NSInvalidArgumentException',
reason: '- [__NSCFDictionary dataUsingEncoding:]:
unrecognized selector sent to instance 0x7987d60'
The code is as followings:
代码如下：
NSData *data = [str dataUsingEncoding:NSASCIIStringEncoding];
//NSUTF8StringEncoding also failed.
NSDictionary *dict = [NSJSONSerialization JSONObjectWithData:data options:kNilOptions error:&error];
In my opinion, this is because str contains new-line character:'\n'.
在我看来，这是因为 str 包含换行符：'\n'。
Am I correct?
我对么？
Would somebody please help me to solve this problem?
有人可以帮我解决这个问题吗？
回答by jmstone617
Your error says that you are trying to send dataUsingEncoding:allowLossyConversion:to an instance of NSDictionary, which doesn't know what to do with that selector. Make sure your strobject is actually a string...
您的错误表明您正在尝试发送dataUsingEncoding:allowLossyConversion:到 的实例NSDictionary，该实例不知道如何处理该选择器。确保您的str对象实际上是一个字符串...
回答by Fernando Cervantes
Try using NSUnicodeStringEncodinginstead of NSASCIIStringEncoding. So replace the line:
尝试使用NSUnicodeStringEncoding代替NSASCIIStringEncoding. 所以替换该行：
NSData *data = [str dataUsingEncoding:NSASCIIStringEncoding];
with this:
有了这个：
NSData *data = [str dataUsingEncoding:NSUnicodeStringEncoding];
回答by Praveen-K
I just checked with my sample string. **If you could have given me your string then i could have checked out with my following sample code.
我刚刚检查了我的示例字符串。**如果您可以给我您的字符串，那么我可以使用以下示例代码进行检查。
NSString *msg = [NSString stringWithFormat:@"tell me \"where\"\n"
"is\n"
"wrong"];
NSData *theData = [msg dataUsingEncoding:NSASCIIStringEncoding];
NSString* theString = [[NSString alloc] initWithData:theData encoding:NSASCIIStringEncoding];
BOOL isValid = [NSJSONSerialization isValidJSONObject:theString];
NSLog(@"Value %d %@",isValid, theString);
For me The value is coming 0 and tell me "where"
对我来说 值即将变为 0 并告诉我“在哪里”
is
是
wrong
错误的
