如何连接两列值并在ios中进行比较

Question

In my entity Contact, I have two columns named firstName & lastName. I want to search for a name entered by user in my DB.

For Eg: If user enters only 'William' I can search either its present in first name or last name and show the result. If the user enters 'William Smith', then I want to get both first name and last name from DB and compares it with search text.

For this i want to use NSPredicate that compares 3 condition:

firstName contains the search text OR
lastName contains the search text OR
firstName+lastName contains the search text.

I used the following predicate for that:

NSString *strSearchType = @"(%@ CONTAINS[cd] '%@' OR %@ CONTAINS[cd] '%@' OR (%@ || %@ CONTAINS[cd] '%@')";

I know "||" is the concatenate operator.

But it gives me the following exception:

  *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Unable to parse the format string "(firstName CONTAINS[cd] 'rus' OR lastName CONTAINS[cd] 'rus' OR ((firstName || lastName) CONTAINS[cd] 'rus'))"'

Am i doing anything wrong ?

Answer 1

You can try following :

firstName contains the search text OR
lastName contains the search text OR
(search text contains the firstName AND search text contains the lastName).

Answer 2

   NSString* stringA=nil;     NSString* stringB=nil; 

// this would give array of string separated by space
 NSArray *searchStrArray = [searchString componentsSeparatedByCharactersInSet:[NSCharacterSet characterSetWithCharactersInString:@" "]];

   if (searchStrArray.count>0) {
        stringA=[searchStrArray objectAtIndex:0];
    }
    if (searchStrArray.count>1) {
        stringB=[searchStrArray objectAtIndex:1];
    }

NSPredicate* predicateA= [NSPredicate predicateWithFormat:@“firstName CONTAINS[c] %@ OR lastName CONTAINS[c] %@",stringA , stringA];

NSPredicate* resultPredicate=predicateA;

if(stringB){
NSPredicate* predicateB= [NSPredicate predicateWithFormat:@“firstName CONTAINS[c] %@ OR lastName CONTAINS[c] %@",stringB , stringB];

            resultPredicate=[NSCompoundPredicate andPredicateWithSubpredicates:[NSArray arrayWithObjects:resultPredicate,predicateB, nil]];

}