知识点---前端处理支持emoji表情
作者：互联网
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>前端处理支持emoji表情</title>
</head>
<body>
<h1>测试</h1>
<textarea rows="10" cols="40" id="text"></textarea>
<button type="" id="enbtn">编码</button>
<button type="" id="debtn">解码</button>
<h2>结果</h2>
<div id="dv"></div>
</body>
</html>
<script>
/**
*
* Base64 encode / decode
*
**/
var Base64 = {
// private property
_keyStr: "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=",
// public method for encoding
encode: function (input) {
var output = "";
var chr1, chr2, chr3, enc1, enc2, enc3, enc4;
var i = 0;
input = Base64._utf8_encode(input);
while (i < input.length) {
chr1 = input.charCodeAt(i++);
chr2 = input.charCodeAt(i++);
chr3 = input.charCodeAt(i++);
enc1 = chr1 >> 2;
enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
enc4 = chr3 & 63;
if (isNaN(chr2)) {
enc3 = enc4 = 64;
} else if (isNaN(chr3)) {
enc4 = 64;
}
output = output +
this._keyStr.charAt(enc1) + this._keyStr.charAt(enc2) +
this._keyStr.charAt(enc3) + this._keyStr.charAt(enc4);
}
return output;
},
// public method for decoding
decode: function (input) {
var output = "";
var chr1, chr2, chr3;
var enc1, enc2, enc3, enc4;
var i = 0;
input = input.replace(/[^A-Za-z0-9\+\/\=]/g, "");
while (i < input.length) {
enc1 = this._keyStr.indexOf(input.charAt(i++));
enc2 = this._keyStr.indexOf(input.charAt(i++));
enc3 = this._keyStr.indexOf(input.charAt(i++));
enc4 = this._keyStr.indexOf(input.charAt(i++));
chr1 = (enc1 << 2) | (enc2 >> 4);
chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
chr3 = ((enc3 & 3) << 6) | enc4;
output = output + String.fromCharCode(chr1);
if (enc3 != 64) {
output = output + String.fromCharCode(chr2);
}
if (enc4 != 64) {
output = output + String.fromCharCode(chr3);
}
}
output = Base64._utf8_decode(output);
return output;
},
// private method for UTF-8 encoding
_utf8_encode: function (string) {
string = string.replace(/\r\n/g, "\n");
var utftext = "";
for (var n = 0; n < string.length; n++) {
var c = string.charCodeAt(n);
if (c < 128) {
utftext += String.fromCharCode(c);
}
else if ((c > 127) && (c < 2048)) {
utftext += String.fromCharCode((c >> 6) | 192);
utftext += String.fromCharCode((c & 63) | 128);
}
else {
utftext += String.fromCharCode((c >> 12) | 224);
utftext += String.fromCharCode(((c >> 6) & 63) | 128);
utftext += String.fromCharCode((c & 63) | 128);
}
}
return utftext;
},
// private method for UTF-8 decoding
_utf8_decode: function (utftext) {
var string = "";
var i = 0;
var c = c1 = c2 = 0;
while (i < utftext.length) {
c = utftext.charCodeAt(i);
if (c < 128) {
string += String.fromCharCode(c);
i++;
}
else if ((c > 191) && (c < 224)) {
c2 = utftext.charCodeAt(i + 1);
string += String.fromCharCode(((c & 31) << 6) | (c2 & 63));
i += 2;
}
else {
c2 = utftext.charCodeAt(i + 1);
c3 = utftext.charCodeAt(i + 2);
string += String.fromCharCode(((c & 15) << 12) | ((c2 & 63) << 6) | (c3 & 63));
i += 3;
}
}
return string;
}
}
//编码
document.getElementById('enbtn').onclick = encodeFn;
function encodeFn() {
// 获取 value
var enval = document.getElementById('text').value;
// 获取 value 中所有表情
var reg = enval.match(/[\uD83C|\uD83D|\uD83E][\uDC00-\uDFFF][\u200D|\uFE0F]|[\uD83C|\uD83D|\uD83E][\uDC00-\uDFFF]|[0-9|*|#]\uFE0F\u20E3|[0-9|#]\u20E3|[\u203C-\u3299]\uFE0F\u200D|[\u203C-\u3299]\uFE0F|[\u2122-\u2B55]|\u303D|[\A9|\AE]\u3030|\uA9|\uAE|\u3030/ig);
console.log(reg)
// 将所有表情转成 base 64
var emojiBaseArr = reg.map(function (v) {
return '[' + Base64.encode(v) + ']'
})
console.log(emojiBaseArr);
// 替换文本中所有表情
for (var i = 0; i < emojiBaseArr.length; i++) {
// 相当于每次替换字符串中的第一个
var str = enval.replace(/[\uD83C|\uD83D|\uD83E][\uDC00-\uDFFF][\u200D|\uFE0F]|[\uD83C|\uD83D|\uD83E][\uDC00-\uDFFF]|[0-9|*|#]\uFE0F\u20E3|[0-9|#]\u20E3|[\u203C-\u3299]\uFE0F\u200D|[\u203C-\u3299]\uFE0F|[\u2122-\u2B55]|\u303D|[\A9|\AE]\u3030|\uA9|\uAE|\u3030/, emojiBaseArr[i]);
// 将替换后的值重新赋值给 enval
enval = str;
}
console.log(enval);
return enval;
}
//解码
document.getElementById('debtn').onclick = function () {
// 前端做了处理 后端不需要做任何操作，只需要原封不动的返回来即可 （ 假设获取后台返回的值 ）
var deval = encodeFn()
console.log(deval);
// 正则获取所有中括号中长度为8位的字符（包括中括号）
var res = deval.match(/\[[0-9a-zA-Z]{8}\]|\[[0-9a-zA-Z\+]{8}|\[[0-9a-zA-Z\+\/]{8}/g);
console.log(res);
// 数组中的元素两边的中括号去掉，得到新的数组
var arr = res.map(function (v) {
return v.substr(1, 8)
})
console.log(arr);
// 将新数组中的每个元素解码，得到新的数组
var deArr = arr.map(function (v) {
return Base64.decode(v);
})
console.log(deArr);
// 将解码后的元素和文本中正则匹配到的一一替换
for (var i = 0; i < deArr.length; i++) {
var decode = deval.replace(/\[[0-9a-zA-Z]{8}\]|\[[0-9a-zA-Z\+]{8}\]|\[[0-9a-zA-Z\+\/]{8}/, deArr[i]);
deval = decode;
}
console.log(deval);
// 渲染
document.getElementById('dv').innerHTML = deval
}
</script>
标签：知识点,keyStr,charAt,前端,utftext,._,var,input,emoji 来源： https://www.cnblogs.com/liaohongwei/p/10729388.html