convert NSTaggedPointerString to NSString

Question

I had called an interface of Baidu to check id Number, however the value of Sex returned with sex = M, without "" around the M in JSON, when I use NSString in module to store it and then print the class name of this sex property, it printed as NSTaggedPointerString, I doubt how to convert it to a String to use it. Anyone have good ideas?

Antisepticize

{ errNum = 0; retData = { address = "\U6e56\U5317\U7701\U7701\U76f4\U8f96\U53bf\U7ea7\U884c\U653f\U533a\U5212\U4ed9\U6843\U5e02"; birthday = "1989-07-10"; sex = M; }; retMsg = success; } This is the JSON that returns – Antisepticize

Answer 1

NSTaggedPointerString is already an NSString, it's just a subclass. You can use it anywhere you can use an NSString, without conversion.

Rheta

Thanks, I just find it as I used the wrong arguments in swift, it should use %@ just as Obj-C but I used the %s instead. I fixed the error. – Antisepticize

In my cace,when does not convert than makes warnning \n "Incompatible pointer types initializing ~~" – Sher

That's a different issue entirely. NSTaggedPointerString is about the dynamic type of the object. Your issue is about the type you have written in your source code. – Rheta

po [NSClassFromString(@"NSTaggedPointerString") superclass] will prove your answer. – Taken

@Rheta could you explain a little bit more about the the issue you described? Since I need to save the string into file but with NSTaggedPointerString it seemed not be saved correctly. – Mendes

That sounds like something else. The issue I mentioned in the comments wouldn't apply to anything while the app is running, only when it's being compiled. – Rheta

Try converting a number to a string and pass it on from one view controller to another, without doing something like stringWithString beforehand. You will see how "anywhere" is not actually anywhere. – Repentance

I've done many things like that. It works fine. You have some other more subtle bug there that is being worked around. – Rheta

Answer 2

I have encountered places where NSTaggedPointerString cannot be used as a NSString, such as when creating an NSDictionary. In those cases use stringWithString::

NSString* <# myNSString #> = [NSString stringWithString:<# myNSTaggegedString #>];

Misunderstood

I found it easier to just say NSDictionary *aDict = @{[myvar valueForKey:@"item"] since the .property doesn't work well. KVO to the rescue – Izanagi

Answer 3

I had this same issue multiple times. It would seem that type inference for NSDictionary is not an exact science. What I do is specifically ask if the object responds to a particular method. For example if I am looping through parsing some JSON and I am attempting to access a value of type NSString:

NSString * string;
if ([[dict objectForKey:@"value"] respondsToSelector:@selector(stringValue)]) {
    string = [[dict objectForKey:@"value"] stringValue];
}
else {
   string = [NSString stringWithString:[dict objectForKey:@"value"]];
}
documentFile.documentRevision = string;

Impetuosity

Answer 4

In my case son {"count":"123"} I got error. Solved:

// Data was created, we leave it to you to display all of those tall tales!
// NSLog(@«data: %@", [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding]);

NSDictionary * json  = [NSJSONSerialization JSONObjectWithData:data options:0 error:nil];
if ([json isKindOfClass:[NSDictionary class]]){ //Added instrospection as suggested in comment.
                  NSArray *dicArray = json[@"count"];
                   NSLog(@"=:%@", dicArray);

 }

Retentive

Answer 5

for Swift 3 or 4

String(stringInterpolationSegment: taggedPointerString) 

Gehlbach