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
// Return 1 if a > b
// Return -1 if a < b
// Return 0 if a == b
function compare(a, b) {
if (a === b) {
return 0;
}
var a_components = a.split(".");
var b_components = b.split(".");
var len = Math.min(a_components.length, b_components.length);
// loop while the components are equal
for (var i = 0; i < len; i++) {
// A bigger than B
if (parseInt(a_components[i]) > parseInt(b_components[i])) {
return 1;
}
// B bigger than A
if (parseInt(a_components[i]) < parseInt(b_components[i])) {
return -1;
}
}
// If one's a prefix of the other, the longer one is greater.
if (a_components.length > b_components.length) {
return 1;
}
if (a_components.length < b_components.length) {
return -1;
}
// Otherwise they are the same.
return 0;
}
console.log(compare("1", "2"));
console.log(compare("2", "1"));
console.log(compare("1.0", "1.0"));
console.log(compare("2.0", "1.0"));
console.log(compare("1.0", "2.0"));
console.log(compare("1.0.1", "1.0"));
其他回答
function compare(versionA: string | undefined, versionB: string | undefined, operator: string = '>') {
if (versionA === undefined || versionB === undefined) {
return false
}
const listA = versionA.split('.')
const listB = versionB.split('.')
let a = []
let b = []
for (let i = 0; i < listA.length; i++) {
a.push(parseInt(listA[i].replace(/\D/g, ''), 10))
b.push(parseInt(listB[i].replace(/\D/g, ''), 10))
}
for (let i = 0; i < listA.length; i++) {
switch (operator) {
case '>':
case '>=':
if (a[i] === b[i]) {
continue
}
if (a[i] > b[i]) {
return true
}
if (a[i] < b[i]) {
return false
}
break
case '<':
case '<=':
if (a[i] === b[i]) {
continue
}
if (a[i] > b[i]) {
return false
}
if (a[i] < b[i]) {
return true
}
break
case '=':
if (a[i] > b[i]) {
return false
}
if (a[i] < b[i]) {
return false
}
break
}
}
switch (operator) {
case '>':
return false
case '<':
return false
case '=':
case '>=':
case '<=':
return true
}
}
你可以遍历每个以句点分隔的字符并将其转换为int类型:
var parts = versionString.split('.');
for (var i = 0; i < parts.length; i++) {
var value = parseInt(parts[i]);
// do stuffs here.. perhaps build a numeric version variable?
}
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;
}
我必须比较我的扩展版本，但我没有 在这里找到一个可行的解决方案。在比较1.89 > 1.9或1.24.1 == 1.240.1时，几乎所有提议的期权都被打破了
这里，我从仅在最后的记录1.1 == 1.10和1.10.1 > 1.1.1中0下降的事实开始
compare_version = (new_version, old_version) => {
new_version = new_version.split('.');
old_version = old_version.split('.');
for(let i = 0, m = Math.max(new_version.length, old_version.length); i<m; i++){
//compare text
let new_part = (i<m-1?'':'.') + (new_version[i] || 0)
, old_part = (i<m-1?'':'.') + (old_version[i] || 0);
//compare number (I don’t know what better)
//let new_part = +((i<m-1?0:'.') + new_version[i]) || 0
//, old_part = +((i<m-1?0:'.') + old_version[i]) || 0;
//console.log(new_part, old_part);
if(old_part > new_part)return 0; //change to -1 for sort the array
if(new_part > old_part)return 1
}
return 0
};
compare_version('1.0.240.1','1.0.240.1'); //0
compare_version('1.0.24.1','1.0.240.1'); //0
compare_version('1.0.240.89','1.0.240.9'); //0
compare_version('1.0.24.1','1.0.24'); //1
我不是一个大专家，但我构建了简单的代码来比较两个版本，将第一个返回值更改为-1以对版本数组进行排序
['1.0.240', '1.0.24', '1.0.240.9', '1.0.240.89'].sort(compare_version)
//results ["1.0.24", "1.0.240", "1.0.240.89", "1.0.240.9"]
和短版本的比较全字符串
c=e=>e.split('.').map((e,i,a)=>e[i<a.length-1?'padStart':'padEnd'](5)).join('');
//results " 1 0 2409 " > " 1 0 24089 "
c('1.0.240.9')>c('1.0.240.89') //true
如果您有意见或改进，请不要犹豫提出建议。
这里找不到我想要的函数。所以我自己写了。这就是我的贡献。我希望有人觉得它有用。
优点:
处理任意长度的版本字符串。'1'或'1.1.1.1.1'。 如果没有指定，则默认为0。仅仅因为字符串更长并不意味着它是一个更大的版本。(“1”应与“1.0”和“1.0.0.0”相同。) 比较数字而不是字符串。('3'<'21'应为真。不是假的。) 不要把时间浪费在无用的比较上。(比较for ==) 你可以选择你自己的比较器。
缺点:
它不处理版本字符串中的字母。(我不知道这是怎么回事?)
我的代码，类似于Jon接受的答案:
function compareVersions(v1, comparator, v2) {
"use strict";
var comparator = comparator == '=' ? '==' : comparator;
if(['==','===','<','<=','>','>=','!=','!=='].indexOf(comparator) == -1) {
throw new Error('Invalid comparator. ' + comparator);
}
var v1parts = v1.split('.'), v2parts = v2.split('.');
var maxLen = Math.max(v1parts.length, v2parts.length);
var part1, part2;
var cmp = 0;
for(var i = 0; i < maxLen && !cmp; i++) {
part1 = parseInt(v1parts[i], 10) || 0;
part2 = parseInt(v2parts[i], 10) || 0;
if(part1 < part2)
cmp = 1;
if(part1 > part2)
cmp = -1;
}
return eval('0' + comparator + cmp);
}
例子:
compareVersions('1.2.0', '==', '1.2'); // true
compareVersions('00001', '==', '1.0.0'); // true
compareVersions('1.2.0', '<=', '1.2'); // true
compareVersions('2.2.0', '<=', '1.2'); // false
