Come per analizzare le stringhe in Objective C

Question

Qualcuno può aiutarmi a estrarre valore timestamp int da questa stringa "/ Data (1.242.597,6 milioni) /" in Objective C

Vorrei ottenere 1242597600000.

Thx

Answer 1

Un metodo semplice:

NSString *timestampString = @"\/Date(1242597600000)\/"; 
NSArray *components = [timestampString componentsSeparatedByString:@"("]; 
NSString *afterOpenBracket = [components objectAtIndex:1]; 
components = [afterOpenBracket componentsSeparatedByString:@")"]; 
NSString *numberString = [components objectAtIndex:0]; 
long timeStamp = [numberString longValue]; 

in alternativa, se si conosce la stringa sarà sempre la stessa lunghezza e formato, è possibile utilizzare:

NSString *numberString = [timestampString substringWithRange:NSMakeRange(7,13)]; 

e un altro metodo:

NSRange openBracket = [timestampString rangeOfString:@"("]; 
NSRange closeBracket = [timestampString rangeOfString:@")"]; 
NSRange numberRange = NSMakeRange(openBracket.location + 1, closeBracket.location - openBracket.location - 1); 
NSString *numberString = [timestampString substringWithRange:numberRange]; 

Answer 2

C'è più di un modo per farlo. Ecco un suggerimento usando un NSScanner;

NSString *dateString = @"\/Date(1242597600000)\/"; 
NSScanner *dateScanner = [NSScanner scannerWithString:dateString]; 
NSInteger timestamp; 

if (!([dateScanner scanInteger:&timestamp])) { 
    // scanInteger returns NO if the extraction is unsuccessful 
    NSLog(@"Unable to extract string"); 
} 

// If no error, then timestamp now contains the extracted numbers. 

Answer 3

NSCharacterSet* nonDigits = [[NSCharacterSet decimalDigitCharacterSet] invertedSet]; 
NSString* digitString = [timestampString stringByTrimmingCharactersInSet:nonDigits]; 
return [digitString longValue];