判断是否含有emoij表情：

function isEmojiCharacter(substring) {  

  for ( var i = 0; i < substring.length; i++) {  
    var hs = substring.charCodeAt(i);  
    if (0xd800 <= hs && hs <= 0xdbff) {  
        if (substring.length > 1) {  
            var ls = substring.charCodeAt(i + 1);  
            var uc = ((hs - 0xd800) * 0x400) + (ls - 0xdc00) + 0x10000;  
            if (0x1d000 <= uc && uc <= 0x1f77f) {  
                return true;  
            }  
        }  
    } else if (substring.length > 1) {  
        var ls = substring.charCodeAt(i + 1);  
        if (ls == 0x20e3) {  
            return true;  
        }  
    } else {  
        if (0x2100 <= hs && hs <= 0x27ff) {  
            return true;  
        } else if (0x2B05 <= hs && hs <= 0x2b07) {  
            return true;  
        } else if (0x2934 <= hs && hs <= 0x2935) {  
            return true;  
        } else if (0x3297 <= hs && hs <= 0x3299) {  
            return true;  
        } else if (hs == 0xa9 || hs == 0xae || hs == 0x303d || hs == 0x3030  
                || hs == 0x2b55 || hs == 0x2b1c || hs == 0x2b1b  
                || hs == 0x2b50) {  
            return true;  
        }  
    }  
}  
} 

过滤掉表情：

function filteremoji(){
var ranges = [
    '\ud83c[\udf00-\udfff]', 
    '\ud83d[\udc00-\ude4f]', 
    '\ud83d[\ude80-\udeff]'
];
var emojireg = $("#emoji_input").val();
emojireg = emojireg .replace(new RegExp(ranges.join('|'), 'g'), ''));
}

别忘了外面的} 不知道为什么没进去