How to check if UITextFields are empty?

I think something like this is what you want. It's just using isEqualToString: to check if the string is empty.

NSString *temp1 = number1.text;
NSString *temp2 = number2.text;
... ///< temp3, etc

if ([temp1 isEqualToString:@""]) {
    // temp1 not valid
} else if ([temp2 isEqualToString:@""]) {
    // temp2 not valid
} ... {
    // temp3, etc
} else {
    // Valid
}

You may want to trim whitespace characters when grabbing temp1 so that @" " would also be blank. For that, take a look at NSString's stringByTrimmingCharactersInSet: method like so:

NSString *temp1 = [number1.text stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceCharacterSet]];

Update:

If you want to do it with an array you could do something like:

NSMutableArray *array = [NSMutableArray arrayWithCapacity:0];
[array addObject:number1.text];
[array addObject:number2.text];
... ///< number3, etc

BOOL ok = YES;
[array enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
    if ([obj isEqualToString:@""]) {
        ok = NO;
        *stop = YES;
    }
}];

if (ok) {
    // Valid
} else {
    // Not valid
}

I am supposing UITextField variable as *tfield so here is the solution

if (tfield.text.length > 0 || tfield.text != nil || ![tfield.text isEqual:@""])
{
   //do your work
}
else
{
   //through error
}

or you could just call

[myTextField hasText];

which will return NO if the field is empty.