Finding Similar Strings without case sensitivity - iPhone

Question

In my application there is a tableView & a search bar.

I have an NSMutable array to fill data in tableView.

Now, whatever user types in a search bar - data should be filter accordingly & tableView should be reloaded.

I have implemented following code in my application on textField resignFirstResponder.

My question is within this code.

-(BOOL)textFieldShouldReturn:(UITextField*)txt
{
      [txt resignFirstResponder];
      // on textfield resign searchData will be called 
      [self searchData];
      return YES;
}
-(void)searchData
{
       // N -> total elements & i for loop
       NSInteger n=[CategoryDtlArray count],i;
       //CategoryDtl is my custom class & it's objects are stored in my array
       CategoryDtl *tmpCat;
       // dtl string -> which is needed for comparison
       NSString *dtl;
       for (i=0; i<n; i++)
       {
               // got the object from array
            tmpCat=(CategoryDtl*)[CategoryDtlArray objectAtIndex:i];
               // got the description from the object for comparison  
            dtl=[NSString stringWithString:tmpCat.Tip_Description];
               // string to search
               NSString *strSrch=[NSString stringWithString:txtSearch.text];
               // now I don't know how to check my object's String
               // is starting with search string or not?
               // if it starts with search string -> it should be displayed in table
               // else not.
               // "How to implement this?"
               // String comparison without case sensitivity
       }
}

Thanks in advance for helping me.

Answer 1

Does this help?

if ([dtl hasPrefix:strSrch])  
{  
    //  match!
}

Answer 2

See NSArray's -filteredArrayUsingPredicate:. You'll pass that an NSPredicate object which compares the array's leaf objects respective string property using a case-insensitive/diacritic compare.