iPhone: How to Extract a Numerical Value from a String?

Question

Is it possible to extract a number from a string. For example, I have a string:

my name is shishir and my number is 98890876478

Can I extract on 98890876478 from the above string?

Or if my string is:

my name is shishir and my number is XXX98890876478XXX

In this condition can I extract `98890876478", which is in between of XXX.

Is it posible to do this?

I am getting a message from a server which should be in the format as above, and I need the numeric value for further operations

Hope for a quick a reply, and hope you guys understand what I am trying to say

Edit:

Here's the code I'm trying to use:

NSString *logString = [NSString stringWithFormat:@"%@",theXML]; 
NSString *digits = [logString stringByTrimmingCharactersInSet:[[NSCharacterSet decimalDigitCharacterSet] invertedSet]]; 
NSLog(@"Message id: %i", [digits intValue]);

which outputs:

2010-05-21 16:37:07.092 sms[5311:207] OK: message-ID XXX110103468XXX
2010-05-21 16:37:07.851 sms[5311:207] Message id: 2

I think its returning two because size==2. I need to retrieve the value between the "XXX".

Answer 1

You can use regex for this: you want to match \d+, that is, a non-zero sequence of digits.

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Otherwise, you can just manually go through the characters in the string and find any contiguous sequence of digits.

Answer 2

I think what you need is NSScanner, this allows you to take out parts of the string.

e.g.

int n;
NSScanner * scanner = [[NSScanner alloc] initWithString:@"Your string 1234"];
[scanner scanInt:&n];

Answer 3

THIS IS WHAT I FINALLY DONE WITH

NSString *newString = [[theXML componentsSeparatedByCharactersInSet: [[NSCharacterSet decimalDigitCharacterSet] invertedSet]] componentsJoinedByString:@""];
----------------------------------------

NSString *newStr = [newString substringWithRange:NSMakeRange(1, [newString length]-1)];
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And I am done.

Thanks a lot all of u ... regards shishir