Best way to Declare & Initialize String Variable in Objective C

Question

I am new to Objective C. we can create String Object by one of these. can anybody tell difference & which is best,simplest way to doing this?

NSString *simpleString = @"This is a simple string";
NSString *anotherString = [NSString stringWithString:@"This is another simple string"];
NSString *oneMorestring = [[NSString alloc] initWithString:@"One more!"];
NSMutableString *mutableOne = [NSMutableString stringWithString:@"Mutable String"];
NSMutableString *anotherMutableOne =[[NSMutableString alloc] initWithString:@"A retained one"];
NSMutableString *thirdMutableOne =[NSMutableString stringWithString:simpleString];

Siddiq · Accepted Answer · 2012-11-28 08:09:50Z

2

The First method is the simplest and best method for creating string instance if the string is constant. The first method is also prefer as it follow Modern Objectice-C Language.

The Main deference between NSString and NSMutableString is that NSString object is constant. and we can't change or update its value. But NSMutableString has property to change or updates its value.

answered Nov 28, 2012 at 8:09

Siddiq

3932 silver badges8 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Ryan Ballantyne · Accepted Answer · 2012-11-28 08:04:56Z

2

It really depends on what you want to do.

For simply creating a string from a constant, your first example is best.

stringWithString pretty much just creates a copy of a string, so I don't use it much.

You might want to check out stringWithFormat and stringByAppendingString. Those are two that I use most often.

If you enable ARC, then you don't need to worry about retaining strings. Alloc/init or class factory methods are essentially equivalent under ARC, so use whichever you like best.

answered Nov 28, 2012 at 8:04

Ryan Ballantyne

4,1033 gold badges28 silver badges28 bronze badges

Comments

Anoop Vaidya · Accepted Answer · 2012-11-28 08:08:27Z

1

There is nothing a best way... It is upto our requirement. However most of the time we opt for manual allocated and initized version of NSString or NSMutableString.

First 3 are Constant String, next three are String which you can manipulate.

Line number 1: is simply a const string.

Line number 2: You are copying a const string you anotherString.

Line number 3: You are manually allocating and initializing it. Its upto you or ARC(compiler) to release it.

Similarly with rest Mutable versions.

answered Nov 28, 2012 at 8:08

Anoop Vaidya

46.6k15 gold badges115 silver badges144 bronze badges

Collectives™ on Stack Overflow

Best way to Declare & Initialize String Variable in Objective C

3 Answers 3

Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related