Formating a large amount of data in monoTouch

Question

So in my current project I download a large text file that contains a lot of data. Now I have to search trough that file and check if it contains a number that the user entered. In objective-c this would look like this:

        NSString *securityCodeData = [[NSUserDefaults standardUserDefaults] stringForKey:@"securityCodeData"];

        NSString *trackTraceFileUrlName = [NSString stringWithFormat:@"http://plex.janssen1877.com/app/life/%@",securityCodeData];
        NSData *tmpData = [NSData dataWithContentsOfURL:[NSURL URLWithString:trackTraceFileUrlName] ];



        //convert data to string
        NSString *tmpString = [[NSString alloc] initWithData:tmpData encoding:NSUTF8StringEncoding];
        NSArray *piecesArray = [tmpString componentsSeparatedByString:@"\n"];
        NSMutableArray *trackTraceContent = [NSMutableArray arrayWithArray:piecesArray];
        NSLog(@"RAW:%@",trackTraceContent);

        /*Filtering array for referance*/
        NSPredicate *findStringWithReference = [NSPredicate predicateWithFormat:@"SELF CONTAINS [cd] %@",cRText.text];
        NSArray *trackTraceContentFiltered = [trackTraceContent filteredArrayUsingPredicate:findStringWithReference];
        NSLog(@"Filtered:%@",trackTraceContentFiltered);


    if ([trackTraceContentFiltered count] == 0) {
        UIAlertView *invalidCode = [[UIAlertView alloc] initWithTitle:@"Enter a valid reference number!"
                                                              message:@"Please enter a valid reference number so we can provide the correct information for you."
                                                             delegate:nil
                                                    cancelButtonTitle:@"Close"
                                                    otherButtonTitles:nil];
        [invalidCode show];

    }

What would be the best way to do this in monoTouch? I already tryed some code but its still not right:

void GetTrackTraceData ()
        {


            //Collecting Trace and Trace data from link + security code and converting Track and Trace data into string
            string TracTraceDataString = NSString.FromData (NSData.FromUrl 
                                                    (NSUrl.FromString ("http://plex.janssen1877.com/app/life/" + NSUserDefaults.StandardUserDefaults ["SecurityToken"])), 
                                                     NSStringEncoding.UTF8);

            //Seperating the string and putting each object in the
            string[] TrackTraceDataArray = TracTraceDataString.Split (new char[] { '\n' });

            var TrackTraceFilteredArray = TrackTraceDataArray.Where (x => x.Contains (RefNr.Text));

            if (TrackTraceFilteredArray == null) {

                UIAlertView InvalidAlert = new UIAlertView ("Reference number invalid", "The reference number that you have entered is not linked to the current security code. You can change your security code in the settings.", null, "OK", null);
                InvalidAlert.Show ();
            }else{
                this.PerformSegue ("PushToTrackTraceDetails", this);
            }


            foreach (string s in TrackTraceFilteredArray)
                Console.WriteLine (s);





        }

TrackTraceFilteredArray is never null for some reason. Or do I have to implement this in a different way? Is this code properly written? Im new to c#/MonoTouch so I think it could maybe use some optimisation. Here is an example of data that is stored in the textfile:

51405199 0001055479      1302180721 210005     dossier aangemaakt EDI                                                                 
51403415 0001049498      1302150503 TOMTOM101  Order 51403415-3-278065601: ontvangen                                                  
51403415 0001049498      1302151106 TOMTOM241  Order 51403415-3-278065601: gestart                                                    
51403415 0001049498      1302151106 TOMTOM249  Order 51403415-3-278065601: voltooid                                                   
51403577 0001051919      1302150503 TOMTOM101  Order 51403577-3-278065601: ontvangen                                                  
51403577 0001051919      1302151027 TOMTOM241  Order 51403577-3-278065601: gestart                                                    
51403577 0001051919      1302151039 TOMTOM241  Order 51403577-3-278065601: geschatte aankomst 10:57, 18 km op be                      
51403577 0001051919      1302151106 TOMTOM249  Order 51403577-3-278065601: voltooid                                                   
51404608 EK1000204732540 1302151708 TOMTOM101  Order 51404608-2-477100892: ontvangen                                                  
51404608 EK1000204732540 1302151708 TOMTOM101  Order 51404608-3-477100892: ontvangen                                                  
51404772 0001052637      1302150520 210005     dossier aangemaakt EDI                                                                 
51404772 0001052637      1302151732 TOMTOM101  Order 51404772-3-278065684: ontvangen                                                  
51404773 0001052688      1302150520 210005     dossier aangemaakt EDI                                                                 
51404773 0001052688      1302151732 TOMTOM101  Order 51404773-3-278065684: ontvangen                                                  
51404774 0001053872      1302150521 210005     dossier aangemaakt EDI                                                                 
51404775 0001053872      1302150521 210005     dossier aangemaakt EDI                                                                 
51404776 0001052689      1302150521 210005     dossier aangemaakt EDI                                                                 
51404777 0001052690      1302150530 210005     dossier aangemaakt EDI                                                                 
51404778 0001053934      1302150630 210005     dossier aangemaakt EDI                                                                 
51404778 0001053934      1302151733 TOMTOM101  Order 51404778-3-278065681: ontvangen                                                  
51404779 0001053934      1302150630 210005     dossier aangemaakt EDI                                                                 
51404779 0001053934      1302151733 TOMTOM101  Order 51404779-3-278065690: ontvangen                                                  
51404780 0001053934      1302150630 210005     dossier aangemaakt EDI                                                                 
51404780 0001053934      1302151733 TOMTOM101  Order 51404780-3-278065691: ontvangen

Answer 1

Instead of using Where, it seems like you want Any. Any returns a bool if Any matches are found. This way you dont have to check the count.

Answer 2

The LINQ Where clause does not return 1 or null items, it returns an IEnumerablestring> of 0 or more elements (this also means that the variable name 'TrackTraceFilteredArray' is not correct, since it is not an array).

One way to solve this is to create a list and check the count:

var list = new List<string> (TrackTraceFilteredArray);
if (list.Count == 0) {
    // invalid
} else {
    // ok
}