-(BOOL)firstColor:(UIColor*)firstColor secondColor:(UIColor*)secondColor
{
    if (CGColorEqualToColor(firstColor.CGColor, secondColor.CGColor))
    {
        NSLog(@"颜色相同");
        return YES;
    }
    else
    {
        NSLog(@"颜色不同");
        return NO;
    }
}

适用于:
1.控件的颜色与UIColor的判断

  [self firstColor:_startButton.backgroundColor secondColor:[UIColor redColor]];

2.控件之间的颜色判断

  [self firstColor:_startButton.backgroundColor secondColor:_closeButton.backgroundColor];