带有IF语句问题的NSNumber

Question

I am loading data from a server but I have an issue that the value that I am returning is zero(0) while I can't go inside if. Please where would be the problem?

-(void)method1
{
     NSNumber *value = [data objectForKey:@"samount"];
     NSLog(@"number is -%@-", value); //number is -0-
     if (value == 0)
     {
          NSLog(@" OK :) ");
     }
     else 
     {
          NSLog(@"  Bad :( ");
     }
}

Answer 1

Use isEqual:

if ([value isEqual:@(0)])

That will also evaluate correctly in case value is nil (where == comparison with floatValue or similar methods would fail)

Answer 2

value is an object, and more precisely a NSString object (as per your comments in Alladinian's answer), but you are checking its address. You can convert your string to NSNumber with NSNumberFormatter and then check its value or rely on NSString's built-in methods: integerValue , floatValue , etc.

Assuming value is a NSNumber / NSString :

if ([value integerValue] == 0)

See Getting Numeric Values in NSString documentation and Accessing Numeric Values in the NSNumber documentation and pick the method that best suits your data type.