以下是软件版本号:
"1.0", "1.0.1", "2.0", "2.0.0.1", "2.0.1"
我怎么比较呢?
假设正确的顺序是:
"1.0", "1.0.1", "2.0", "2.0.0.1", "2.0.1"
想法很简单… 读第一个数字，然后，第二个，第三个… 但是我不能将版本号转换为浮点数… 你也可以像这样看到版本号:
"1.0.0.0", "1.0.1.0", "2.0.0.0", "2.0.0.1", "2.0.1.0"
这样可以更清楚地看到背后的想法。 但是，我怎样才能把它转换成计算机程序呢?
当前回答
摘自http://java.com/js/deployJava.js:
// return true if 'installed' (considered as a JRE version string) is
// greater than or equal to 'required' (again, a JRE version string).
compareVersions: function (installed, required) {
var a = installed.split('.');
var b = required.split('.');
for (var i = 0; i < a.length; ++i) {
a[i] = Number(a[i]);
}
for (var i = 0; i < b.length; ++i) {
b[i] = Number(b[i]);
}
if (a.length == 2) {
a[2] = 0;
}
if (a[0] > b[0]) return true;
if (a[0] < b[0]) return false;
if (a[1] > b[1]) return true;
if (a[1] < b[1]) return false;
if (a[2] > b[2]) return true;
if (a[2] < b[2]) return false;
return true;
}
其他回答
下面是一个版本，它对版本字符串进行排序，而不分配任何子字符串或数组。由于它分配的对象更少，GC要做的工作也就更少。
有一对分配(允许重用getVersionPart方法)，但是如果您对性能非常敏感，您可以扩展它以完全避免分配。
const compareVersionStrings : (a: string, b: string) => number = (a, b) =>
{
var ia = {s:a,i:0}, ib = {s:b,i:0};
while (true)
{
var na = getVersionPart(ia), nb = getVersionPart(ib);
if (na === null && nb === null)
return 0;
if (na === null)
return -1;
if (nb === null)
return 1;
if (na > nb)
return 1;
if (na < nb)
return -1;
}
};
const zeroCharCode = '0'.charCodeAt(0);
const getVersionPart = (a : {s:string, i:number}) =>
{
if (a.i >= a.s.length)
return null;
var n = 0;
while (a.i < a.s.length)
{
if (a.s[a.i] === '.')
{
a.i++;
break;
}
n *= 10;
n += a.s.charCodeAt(a.i) - zeroCharCode;
a.i++;
}
return n;
}
这是另一种递归算法。
这段代码只使用了Array。shift和递归，这意味着它可以在Internet Explorer 6+中运行。如果你有任何疑问，你可以访问我的GitHub页面。
(function(root, factory) {
if (typeof exports === 'object') {
return module.exports = factory();
} else if (typeof define === 'function' && define.amd) {
return define(factory);
} else {
return root.compareVer = factory();
}
})(this, function() {
'use strict';
var _compareVer;
_compareVer = function(newVer, oldVer) {
var VER_RE, compareNum, isTrue, maxLen, newArr, newLen, newMatch, oldArr, oldLen, oldMatch, zerofill;
VER_RE = /(\d+\.){1,9}\d+/;
if (arguments.length !== 2) {
return -100;
}
if (typeof newVer !== 'string') {
return -2;
}
if (typeof oldVer !== 'string') {
return -3;
}
newMatch = newVer.match(VER_RE);
if (!newMatch || newMatch[0] !== newVer) {
return -4;
}
oldMatch = oldVer.match(VER_RE);
if (!oldMatch || oldMatch[0] !== oldVer) {
return -5;
}
newVer = newVer.replace(/^0/, '');
oldVer = oldVer.replace(/^0/, '');
if (newVer === oldVer) {
return 0;
} else {
newArr = newVer.split('.');
oldArr = oldVer.split('.');
newLen = newArr.length;
oldLen = oldArr.length;
maxLen = Math.max(newLen, oldLen);
zerofill = function() {
newArr.length < maxLen && newArr.push('0');
oldArr.length < maxLen && oldArr.push('0');
return newArr.length !== oldArr.length && zerofill();
};
newLen !== oldLen && zerofill();
if (newArr.toString() === oldArr.toString()) {
if (newLen > oldLen) {
return 1;
} else {
return -1;
}
} else {
isTrue = -1;
compareNum = function() {
var _new, _old;
_new = ~~newArr.shift();
_old = ~~oldArr.shift();
_new > _old && (isTrue = 1);
return _new === _old && newArr.length > 0 && compareNum();
};
compareNum();
return isTrue;
}
}
};
return _compareVer;
});
好吧，我希望这段代码能帮助到一些人。
下面是测试。
console.log(compareVer("0.0.2","0.0.1"));//1
console.log(compareVer("0.0.10","0.0.1")); //1
console.log(compareVer("0.0.10","0.0.2")); //1
console.log(compareVer("0.9.0","0.9")); //1
console.log(compareVer("0.10.0","0.9.0")); //1
console.log(compareVer("1.7", "1.07")); //1
console.log(compareVer("1.0.07", "1.0.007")); //1
console.log(compareVer("0.3","0.3")); //0
console.log(compareVer("0.0.3","0.0.3")); //0
console.log(compareVer("0.0.3.0","0.0.3.0")); //0
console.log(compareVer("00.3","0.3")); //0
console.log(compareVer("00.3","00.3")); //0
console.log(compareVer("01.0.3","1.0.3")); //0
console.log(compareVer("1.0.3","01.0.3")); //0
console.log(compareVer("0.2.0","1.0.0")); //-1
console.log(compareVer('0.0.2.2.0',"0.0.2.3")); //-1
console.log(compareVer('0.0.2.0',"0.0.2")); //-1
console.log(compareVer('0.0.2',"0.0.2.0")); //-1
console.log(compareVer("1.07", "1.7")); //-1
console.log(compareVer("1.0.007", "1.0.07")); //-1
console.log(compareVer()); //-100
console.log(compareVer("0.0.2")); //-100
console.log(compareVer("0.0.2","0.0.2","0.0.2")); //-100
console.log(compareVer(1212,"0.0.2")); //-2
console.log(compareVer("0.0.2",1212)); //-3
console.log(compareVer('1.abc.2',"1.0.2")); //-4
console.log(compareVer('1.0.2',"1.abc.2")); //-5
我也遇到过类似的问题，而且我已经为它创建了一个解决方案。你可以试一试。
如果等于则返回0，如果版本号大于则返回1，如果版本号小于则返回-1
function compareVersion(currentVersion, minVersion) { let current = currentVersion.replace(/\./g," .").split(' ').map(x=>parseFloat(x,10)) let min = minVersion.replace(/\./g," .").split(' ').map(x=>parseFloat(x,10)) for(let i = 0; i < Math.max(current.length, min.length); i++) { if((current[i] || 0) < (min[i] || 0)) { return -1 } else if ((current[i] || 0) > (min[i] || 0)) { return 1 } } return 0 } console.log(compareVersion("81.0.1212.121","80.4.1121.121")); console.log(compareVersion("81.0.1212.121","80.4.9921.121")); console.log(compareVersion("80.0.1212.121","80.4.9921.121")); console.log(compareVersion("4.4.0","4.4.1")); console.log(compareVersion("5.24","5.2")); console.log(compareVersion("4.1","4.1.2")); console.log(compareVersion("4.1.2","4.1")); console.log(compareVersion("4.4.4.4","4.4.4.4.4")); console.log(compareVersion("4.4.4.4.4.4","4.4.4.4.4")); console.log(compareVersion("0","1")); console.log(compareVersion("1","1")); console.log(compareVersion("1","1.0.00000.0000")); console.log(compareVersion("","1")); console.log(compareVersion("10.0.1","10.1"));
两个版本比较
const val = '1.2.3 5.4.3';
const arr = val.split(' ');
let obj = {};
for(let i = 0; i<2; i++) {
const splitArr = arr[i].split('.')
const reduced = splitArr.reduce((pre,
curr)=>parseInt(pre)+parseInt(curr));
obj[i] = reduced;
}
if(obj[0]>obj[1]) {
console.log(arr[0]);
} else {
console.log(arr[1]);
}
这里有一个面向对象的有趣方法:
function versionString(str) {
var parts = str.split('.');
this.product = parts.length > 0 ? parts[0] * 1 : 0;
this.major = parts.length > 1 ? parts[1] * 1 : 0;
this.minor = parts.length > 2 ? parts[2] * 1 : 0;
this.build = parts.length > 3 ? parts[3] * 1 : 0;
this.compareTo = function(vStr){
vStr = this._isVersionString(vStr) ? vStr : new versionString(vStr);
return this.compare(this, vStr);
};
this.toString = function(){
return this.product + "." + this.major + "." + this.minor + "." + this.build;
}
this.compare = function (str1, str2) {
var vs1 = this._isVersionString(str1) ? str1 : new versionString(str1);
var vs2 = this._isVersionString(str2) ? str2 : new versionString(str2);
if (this._compareNumbers(vs1.product, vs2.product) == 0) {
if (this._compareNumbers(vs1.major, vs2.major) == 0) {
if (this._compareNumbers(vs1.minor, vs2.minor) == 0) {
return this._compareNumbers(vs1.build, vs2.build);
} else {
return this._compareNumbers(vs1.minor, vs2.minor);
}
} else {
return this._compareNumbers(vs1.major, vs2.major);
}
} else {
return this._compareNumbers(vs1.product, vs2.product);
}
};
this._isVersionString = function (str) {
return str !== undefined && str.build !== undefined;
};
this._compareNumbers = function (n1, n2) {
if (n1 > n2) {
return 1;
} else if (n1 < n2) {
return -1;
} else {
return 0;
}
};
}
还有一些测试:
var v1 = new versionString("1.0");
var v2 = new versionString("1.0.1");
var v3 = new versionString("2.0");
var v4 = new versionString("2.0.0.1");
var v5 = new versionString("2.0.1");
alert(v1.compareTo("1.4.2"));
alert(v3.compareTo(v1));
alert(v5.compareTo(v4));
alert(v4.compareTo(v5));
alert(v5.compareTo(v5));
