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
例如，如果我们想检查当前jQuery版本是否小于1.8，如果version是"1.10.1"，parseFloat($.ui.version) < 1.8)将会给出错误的结果，因为parseFloat("1.10.1")返回1.1。 字符串比较也会出错，因为"1.8" < "1.10"的结果为false。
所以我们需要一个这样的测试
if(versionCompare($.ui.version, "1.8") < 0){
alert("please update jQuery");
}
下面的函数可以正确地处理这个问题:
/** Compare two dotted version strings (like '10.2.3').
* @returns {Integer} 0: v1 == v2, -1: v1 < v2, 1: v1 > v2
*/
function versionCompare(v1, v2) {
var v1parts = ("" + v1).split("."),
v2parts = ("" + v2).split("."),
minLength = Math.min(v1parts.length, v2parts.length),
p1, p2, i;
// Compare tuple pair-by-pair.
for(i = 0; i < minLength; i++) {
// Convert to integer if possible, because "8" > "10".
p1 = parseInt(v1parts[i], 10);
p2 = parseInt(v2parts[i], 10);
if (isNaN(p1)){ p1 = v1parts[i]; }
if (isNaN(p2)){ p2 = v2parts[i]; }
if (p1 == p2) {
continue;
}else if (p1 > p2) {
return 1;
}else if (p1 < p2) {
return -1;
}
// one operand is NaN
return NaN;
}
// The longer tuple is always considered 'greater'
if (v1parts.length === v2parts.length) {
return 0;
}
return (v1parts.length < v2parts.length) ? -1 : 1;
}
下面是一些例子:
// compare dotted version strings
console.assert(versionCompare("1.8", "1.8.1") < 0);
console.assert(versionCompare("1.8.3", "1.8.1") > 0);
console.assert(versionCompare("1.8", "1.10") < 0);
console.assert(versionCompare("1.10.1", "1.10.1") === 0);
// Longer is considered 'greater'
console.assert(versionCompare("1.10.1.0", "1.10.1") > 0);
console.assert(versionCompare("1.10.1", "1.10.1.0") < 0);
// Strings pairs are accepted
console.assert(versionCompare("1.x", "1.x") === 0);
// Mixed int/string pairs return NaN
console.assert(isNaN(versionCompare("1.8", "1.x")));
//works with plain numbers
console.assert(versionCompare("4", 3) > 0);
看到这里的现场示例和测试套件: http://jsfiddle.net/mar10/8KjvP/
其他回答
replace()函数只替换字符串中的第一个出现项。我们来替换。与,。然后全部删除。然后做，to。再次将其解析为float。
for(i=0; i<versions.length; i++) {
v = versions[i].replace('.', ',');
v = v.replace(/\./g, '');
versions[i] = parseFloat(v.replace(',', '.'));
}
最后，排序:
versions.sort();
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?
}
我的答案比这里的大多数答案都要简洁
/**
* Compare two semver versions. Returns true if version A is greater than
* version B
* @param {string} versionA
* @param {string} versionB
* @returns {boolean}
*/
export const semverGreaterThan = function(versionA, versionB){
var versionsA = versionA.split(/\./g),
versionsB = versionB.split(/\./g)
while (versionsA.length || versionsB.length) {
var a = Number(versionsA.shift()), b = Number(versionsB.shift())
if (a == b)
continue
return (a > b || isNaN(b))
}
return false
}
你可以使用JavaScript的localeCompare方法:
a.localeCompare(b, undefined， {numeric: true})
这里有一个例子:
"1.1".localeCompare("2.1.1"， undefined， {numeric: true}) => -1
"1.0.0".localeCompare("1.0"， undefined， {numeric: true}) =>
"1.0.0".localeCompare("1.0.0"， undefined， {numeric: true}) => 0
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"));
