首先，我们可以得到文本的宽度，这将呈现在标签。然后，我们可以比较宽度与标签的宽度。如果宽度超过，那么字符串被截断，否则不。

• • 更新**

如果标签有行，则计算行数并检查lablewidth * numofLines

UILabel *lblAppTitle = (UILabel*)[self.view viewWithTag:777];    
CGSize stringSize = [lblAppTitle.text sizeWithFont:lblAppTitle.font];

//Count Number of lines
[lblAppTitle sizeToFit];
int numLines = (int)(lblAppTitle.frame.size.height/lblAppTitle.font.leading);

if (stringSize.width > (lblAppTitle.frame.size.width)*numLines)
    NSLog(@"truncated string");
else
    NSLog(@"did not truncate string");

希望这对你有帮助。

NSString *str = @"Hello this is the ...";
NSRange range = [str rangeOfString:@"..."];
if (range.location>0 && range.length == 3) {
    //Found
}

UILabel *lbl ;
 lbl.text = @"Hello..World.";
 NSString * charToCount = @".";
 NSArray * array = [lbl.text componentsSeparatedByString:charToCount];
 if([array count] >= 3)
    NSLog(@"Found");
 else 
    NSLog(@"Not Found");