JavaScript验证输入的字符是否包含表情

以下是验证代码：

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;
            }
        }
    }
}