Objective-C on the Mac L6 - NSString

[findthebug]

good tut, thanks

[davepamn]

I would like a video that show how to

1. substring an NSString

2. compare a NSString

3. replace part of a NSString

[davepamn]

It is time consuming. I was hoping for a quick overview through a tutorial.

[davepamn]

Will you create a second NSString tutorial and cover all the string comparison and substring functions?

[AppleProgramming]

@davepamn Perhaps, but they aren't hard to figure out if you read the NSString class reference in the documentation.

[richardlipp21]

Thanks Lucas for that info but.. I went to the apple dev site and man there are so many method for creating a string. I am not sure wich one?? Can you do a tutorial on this. I know alot of folks would like to see that..

Keep up the good work ..Richard..

[AppleProgramming]

@richardlipp21 I will do one later.

[richardlipp21]

HI lucas.. this is great but how do you get user to input... say... his name or some data.... and then turn that into a string object?? could you please do a tutorial on this???. I have searched the net and there are a lot of people very confused about this. Some use "get" some use "scanf"... but know one seems to know how to do this.. Thanks...

[AppleProgramming]

@richardlipp21 You have to use the C functions and then convert your C string into an NSString using one of the NSString methods (something like stringWithCString:encoding:).

[unholyGothyx]

thank you a lot!!!! but one thing - it's 'va-ya' not 'vee-ah' in via:) x

[ezimerman]

In reference to the NSString *string = [NSString stringWithString:@"A String here"]; ....... What exactly do you mean when you say "temporary objects that will be destroyed after a while" ? How long do these types of objects remain in memory? Thanks!

[AppleProgramming]

@ezimerman I go in depth with object memory in later tutorials, but there is no real exact time autoreleased objects get trashed. In this case it will some time after we call [pool drain], but in something like iOS, it could happen after an "event" which could be just pressing a button. A good rule of thumb is to only use them in something like a method where it will be used quickly or when returning a value (very short term storage). Use alloc init to store values for long periods of time.

[mrnetanell]

Also how can i refer a particular character in the NSString, for example lets say i have the following string "123" and i want to do the following calculation,

int n = (string[0] - '0') + (string[1] - '0');

Thanks a lot.

[AppleProgramming]

@mrnetanell I would look at the NSString class reference. Some methods that might help you out are substringWithRange:, characterAtIndex:, intValue. Just look in the documentation and I'm sure you can find something there that will accomplish the task. Not sure what you were trying to do with the - '0', but there is not need to do that with an NSString.

[mrnetanell]

I want to pass NSString value to another object and this object is a ViewController.

Can you please demonstrate how can i pass NSString to the ViewController set NSString data member in the ViewController, and when exactly i need to release the memory ?

Thanks a lot.

need to pass the NSString to the View Controller and when i need to release the memory ?

Thanks a lot.

[AppleProgramming]

@mrnetanell Have you gotten to the memory management tutorials yet?

[ezimerman]

Is there anything wrong with creating the instance without any methods? Ex:

NSString *myString = @"This is my string";

[AppleProgramming]

@ezimerman Nope, that is perfectly fine. I just show examples with methods because it gives you more flexibility to what you put in your string.

[marcushammar]

This is a great explanation of NSString. I found this video first because I was looking for more information regarding NSString. I then looked at your other videos on Objective-C and they are really good! Thanks a lot for sharing your knowledge :)