how to append the value from picker to textfield

I am having a picker, which displays data from 2 arrays, say like it is a picker with 2 sections.

Now I w开发者_如何学Cant the selected values from both the sections, to appear in a single textfield.

I tried with

textField.text=[[First_Array ObjectAtindex:row]appendString:[Second_Array ObjectAtIndex:row]];

But it gives error “Void Value not ignored as it ought yo be”

Instead of appendString:, use stringByAppendingString:. appendString: is used to modify an NSMutableString in place, it doesn't return a value.