JS生成uuid的四种方法

迷南。 2022-12-30 07:46 139阅读 0赞

在开发过程中，有时候需要js生成全局唯一标识符，在java中可以使用uuid，但是JS中没有现成的函数。  
总结了一下，JS生成唯一标识符的几种方法。

**第一种：**

function uuid() {
    	var s = [];
    	var hexDigits = "0123456789abcdef";
    	for (var i = 0; i < 36; i++) {
    		s[i] = hexDigits.substr(Math.floor(Math.random() * 0x10), 1);
    	}
    	s[14] = "4"; // bits 12-15 of the time_hi_and_version field to 0010
    	s[19] = hexDigits.substr((s[19] & 0x3) | 0x8, 1); // bits 6-7 of the clock_seq_hi_and_reserved to 01
    	s[8] = s[13] = s[18] = s[23] = "-";
    
    	var uuid = s.join("");
    	return uuid;
    }

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**第二种：**

function guid() {
    	return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, function (c) {
    		var r = Math.random() * 16 | 0,
    			v = c == 'x' ? r : (r & 0x3 | 0x8);
    		return v.toString(16);
    	});
    }

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**第三种：**

function guid2() {
    	function S4() {
    		return (((1 + Math.random()) * 0x10000) | 0).toString(16).substring(1);
    	}
    	return (S4() + S4() + "-" + S4() + "-" + S4() + "-" + S4() + "-" + S4() + S4() + S4());
    }

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**第四种：**

/*
    	指定长度和基数
    
    */
    function uuid2(len, radix) {
    	var chars = '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz'.split('');
    	var uuid = [],
    		i;
    	radix = radix || chars.length;
    
    	if (len) {
    		// Compact form
    		for (i = 0; i < len; i++) uuid[i] = chars[0 | Math.random() * radix];
    	} else {
    		// rfc4122, version 4 form
    		var r;
    
    		// rfc4122 requires these characters
    		uuid[8] = uuid[13] = uuid[18] = uuid[23] = '-';
    		uuid[14] = '4';
    
    		// Fill in random data.  At i==19 set the high bits of clock sequence as
    		// per rfc4122, sec. 4.1.5
    		for (i = 0; i < 36; i++) {
    			if (!uuid[i]) {
    				r = 0 | Math.random() * 16;
    				uuid[i] = chars[(i == 19) ? (r & 0x3) | 0x8 : r];
    			}
    		}
    	}
    
    	return uuid.join('');
    }