上一篇文章介绍了一种用雪花算法生成GUID的方法，下面介绍里外一种生成GUID并导出为.txt文件的方法：
话不多说 show you the code !
<!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>GUID</title>
</head>
<body>
<button id="save" type="button">保存GUID文件</button>
<script type="text/javascript">
var GUID_ALPHABET = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ-_";
var GUID_LENGTH = 20,res = [];
var guid = function(a) {
// 改变参数i,想要多少个给多少
for (var i = 0; i < 10; i++) {
a = null != a ? a : GUID_LENGTH;
for (var b = [], str = '', c = 0; c < a; c++) {
b.push(GUID_ALPHABET.charAt(Math.floor(Math.random() * GUID_ALPHABET.length)));
}
str = b.join("");
console.log('str--' + i, str);
res.push(str+'
');
}
return res;
};
document.querySelector('#save').addEventListener('click', saveFile);
function fakeClick(obj) {
var ev = document.createEvent("MouseEvents");
ev.initMouseEvent("click", true, false, window, 0, 0, 0, 0, 0, false, false, false, false, 0, null);
obj.dispatchEvent(ev);
}
function exportRaw(name, data) {
var urlObject = window.URL || window.webkitURL || window;
var export_blob = new Blob([data]);
var save_link = document.createElementNS("http://www.w3.org/1999/xhtml", "a");
save_link.href = urlObject.createObjectURL(export_blob);
save_link.download = name;
fakeClick(save_link);
}
function saveFile() {
var inValue = guid();
exportRaw('guid.txt', inValue);
}
</script>
</body>
</html>
另外，如果想要使生成的GUID更复杂，更有序，可以在这个生成的GUID字符串基础上加 时间戳 或 相关的业务分类字符串 等等。
已经验证该方法生成的大量ID没有重复。