ios 禁止输入表情

当是UITextView时，需要在如下做如下判断：

- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text
{

    if ([self stringContainsEmoji:text]) return NO;
    return NO;
}
           

当是UITextFeild时，需要在如下做如下判断：

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
    if ([self stringContainsEmoji:string]) return NO;

    return YES;
}
           

// 判断是否包含emojy表情
+ (BOOL)stringContainsEmoji:(NSString *)string
{
    
    __block BOOL returnValue = NO;
    
    [string enumerateSubstringsInRange:NSMakeRange(0, [string length]) options:NSStringEnumerationByComposedCharacterSequences usingBlock:
     
     ^(NSString *substring,NSRange substringRange, NSRange enclosingRange, BOOL *stop) {
         
         const unichar hs = [substring characterAtIndex:0];
         
         // surrogate pair
         
         if (0xd800 <= hs && hs <= 0xdbff) {
             
             if (substring.length > 1) {
                 
                 const unichar ls = [substring characterAtIndex:1];
                 
                 const int uc = ((hs - 0xd800) * 0x400) + (ls - 0xdc00) + 0x10000;
                 
                 if (0x1d000 <= uc && uc <= 0x1f77f) {
                     
                     returnValue =YES;
                     
                 }
                 
             }
             
         }else if (substring.length > 1) {
             
             const unichar ls = [substring characterAtIndex:1];
             
             if (ls == 0x20e3) {
                 
                 returnValue =YES;
                 
             }
             
         }else {
             
             // non surrogate
             
             if (0x2100 <= hs && hs <= 0x27ff) {
                 
                 returnValue =YES;
                 
             }else if (0x2B05 <= hs && hs <= 0x2b07) {
                 
                 returnValue =YES;
                 
             }else if (0x2934 <= hs && hs <= 0x2935) {
                 
                 returnValue =YES;
                 
             }else if (0x3297 <= hs && hs <= 0x3299) {
                 
                 returnValue =YES;
                 
             }else if (hs == 0xa9 || hs == 0xae || hs == 0x303d || hs == 0x3030 || hs == 0x2b55 || hs == 0x2b1c || hs == 0x2b1b || hs == 0x2b50) {
                 
                 returnValue =YES;
                 
             }
             
         }
         
     }];
    
    return returnValue;
    
}