将文本和表情标签分开，放到数组里面

- (void)getImageRange:(NSString *)message array:(NSMutableArray *)array
{
    NSRange range=[message rangeOfString:kImageBeginMark];
    NSRange range1=[message rangeOfString:kimageEndMark];
    //判断当前字符串是否还有表情的标志。
    if (range.length>0 && range1.length>0)
    {
        if (range.location > 0)
        {
            [array addObject:[message substringToIndex:range.location]];
            [array addObject:[message substringWithRange:NSMakeRange(range.location, range1.location+1-range.location)]];
            NSString *str=[message substringFromIndex:range1.location+1];
            [self getImageRange:str array:array];
        }
        else
        {
            NSString *nextstr=[message substringWithRange:NSMakeRange(range.location, range1.location+1-range.location)];
            //排除文字是“”的
            if (![nextstr isEqualToString:@""])
            {
                [array addObject:nextstr];
                NSString *str=[message substringFromIndex:range1.location+1];
                [self getImageRange:str array:array];
            }
            else
            {
                return;
            }
        }
    }
    else if (message != nil)
    {
        [array addObject:message];
    }
}

创建

- (id)initWithText:(NSString *)text
{
    NSMutableParagraphStyle *paragraph = [[NSMutableParagraphStyle alloc] init];
    paragraph.lineSpacing = 4;
    paragraph.lineBreakMode = NSLineBreakByCharWrapping;
    
    NSDictionary *attributes = @{NSFontAttributeName : [UIFont systemFontOfSize:16],
                                 NSParagraphStyleAttributeName : paragraph};
    
    NSMutableAttributedString *string = [[NSMutableAttributedString alloc] initWithString:@""];
    
    NSMutableArray *array = [[NSMutableArray alloc] init];
    [self getImageRange:text array:array];
    
    for (NSString *item in array)
    {
        if ([item hasPrefix:kImageBeginMark] && [item hasSuffix:kimageEndMark])
        {
            NSTextAttachment *textAttachment = [[NSTextAttachment alloc] initWithData:nil ofType:nil];
            [textAttachment setImage:[UIImage imageNamed:item]];
            [textAttachment setBounds:CGRectMake(0, -5, 25, 25)];
        
            NSAttributedString *attrStr = [NSAttributedString attributedStringWithAttachment:textAttachment];
            [string appendAttributedString:attrStr];
        }
        else
        {
            NSAttributedString *attrStr = [[NSAttributedString alloc] initWithString:item attributes:attributes];
            [string appendAttributedString:attrStr];
        }
    }
}