stringwithformat

I have the following code: double d1 = 12.123456789012345; NSString *test1 = [NSString stringWithFormat:@"%f", d1]; // string is: 12.123457 NSString *test1 = [NSString stringWithFormat:@"%g", d1]; // string is: 12.1235 How do I get a string value that is exactly the same as d1? It may help you to take a look at Apple's guide to String Format Specifiers . %f 64-bit floating-point number %g 64-bit floating-point number (double), printed in the style of %e if the exponent is less than –4 or greater than or equal to the precision, in the style of %f otherwise Also read up on floating point (in

I found something strange when trying to use width specifiers with %@ . They work fine in NSLog but not with NSString stringWithFormat: . Example: NSString *rightAligned = @"foo"; NSString *leftAligned = @"1"; NSLog(@"| %15@ | %-15@ |", rightAligned, leftAligned); And you get the expected output of: | foo | 1 | But replace the NSLog with stringWithFormat: : NSString *test = [NSString stringWithFormat:@"| %15@ | %-15@ |", rightAligned, leftAligned]; And the value of test is incorrectly: | foo | 1 | If I change this to use %s and cStringUsingEncoding: then it works: NSString *test2 = [NSString

In our current implementation we want to change our string arguments (Push notification loc-args) and add new arguments. But we want user's of our old Versions to still use argument #3 and for new user's we want to user argument #4. So in our new implementation we have following code : NSString *format = @"%2$@, %1$@ ,%4$@"; NSArray *arg = @[@"Argument 1", @"Argument 2",@"Argument 3",@"Argument 4"]; NSString *ouptput = [NSString stringWithFormat:format, arg[0], arg[1], arg[2], arg[3]]; OutPut: Argument 2, Argument 1 ,Argument 3 We are expecting it to be Argument 2, Argument 1 ,Argument 4 How

This question already has an answer here: How to add percent sign to NSString 7 answers How can I add a percent to my stringWithFormat function? For example, I'd like to have the following: float someFloat = 40.233f; NSString *str = [NSString stringWithFormat:@"%.02f%",someFloat]; This should cause the string to be: 40.23% But it is not the case. How can I achieve this? % being the character beginning printf-style formats, it simply needs to be doubled: float someFloat = 40.233f; NSString *str = [NSString stringWithFormat:@"%.02f%%",someFloat]; spolu The escape code for a percent sign is “%%”,

Based on this SO question asked a few hours ago, I have decided to implement a swizzled method that will allow me to take a formatted NSString as the format arg into stringWithFormat , and have it not break when omitting one of the numbered arg references ( %1$@, %2$@ ) I have it working, but this is the first copy, and seeing as this method is going to be potentially called hundreds of thousands of times per app run, I need to bounce this off of some experts to see if this method has any red flags, major performance hits, or optimizations #define NUMARGS(...) (sizeof((int[]){__VA_ARGS__})