获取javascript中矩阵的所有可能选项

我在JavaScript中有一个“item”对象，该项可以有如下设置 颜色、大小等

我需要得到一个数组中所有可能的组合

假设我们有一个项目如下所示：

var newItem = {
    name: 'new item',
    Settings: [
        {name: 'color', values: ['green', 'blue', 'red']},
        {name: 'size',  values: ['15', '18', '22']},
        {name: 'gender',values: ['male', 'female']}
    ]
};

我需要以某种方式得到这个：

[
    [{SettingName:'color',value:'green'},{SettingName:'size',value:'15'},{SettingName:'gender',value:'male'}],
    [{SettingName:'color',value:'blue'},{SettingName:'size',value:'15'},{SettingName:'gender',value:'male'}],
    [{SettingName:'color',value:'red'},{SettingName:'size',value:'15'},{SettingName:'gender',value:'male'}],
    [{SettingName:'color',value:'green'},{SettingName:'size',value:'18'},{SettingName:'gender',value:'male'}],
    [{SettingName:'color',value:'blue'},{SettingName:'size',value:'18'},{SettingName:'gender',value:'male'}],
    [{SettingName:'color',value:'red'},{SettingName:'size',value:'18'},{SettingName:'gender',value:'male'}],
    [{SettingName:'color',value:'green'},{SettingName:'size',value:'22'},{SettingName:'gender',value:'male'}],
    [{SettingName:'color',value:'blue'},{SettingName:'size',value:'22'},{SettingName:'gender',value:'male'}],
    [{SettingName:'color',value:'red'},{SettingName:'size',value:'22'},{SettingName:'gender',value:'male'}],
    [{SettingName:'color',value:'green'},{SettingName:'size',value:'15'},{SettingName:'gender',value:'female'}],
    [{SettingName:'color',value:'blue'},{SettingName:'size',value:'15'},{SettingName:'gender',value:'female'}],
    [{SettingName:'color',value:'red'},{SettingName:'size',value:'15'},{SettingName:'gender',value:'female'}],
    [{SettingName:'color',value:'green'},{SettingName:'size',value:'18'},{SettingName:'gender',value:'female'}],
    [{SettingName:'color',value:'blue'},{SettingName:'size',value:'18'},{SettingName:'gender',value:'female'}],
    [{SettingName:'color',value:'red'},{SettingName:'size',value:'18'},{SettingName:'gender',value:'female'}],
    [{SettingName:'color',value:'green'},{SettingName:'size',value:'22'},{SettingName:'gender',value:'female'}],
    [{SettingName:'color',value:'blue'},{SettingName:'size',value:'22'},{SettingName:'gender',value:'female'}],
    [{SettingName:'color',value:'red'},{SettingName:'size',value:'22'},{SettingName:'gender',value:'female'}]
]

---

这是一个很好的面试问题。
有关运行示例，请参见

getAllPermutations(newItem);

function getAllPermutations(item) {
    var permutations = [];

    getAllPermutations0(item, permutations, []);
    console.log(permutations);
}

function getAllPermutations0(item, permutations, array) {
    if (array && array.length === item.Settings.length) {
        permutations.push(array.slice()); // The slice clone the array
        return;
    }

    var index =  array.length;
    var setting = item.Settings[index];

    for (var i = 0; i < setting.values.length; i++) {
        if (index === 0)
            array =  [];

        var currValue = setting.values[i];

        array.push({
            SettingName: setting.name,
            value: currValue
        });

        getAllPermutations0(item, permutations, array);
        array.pop(); // pop the old one first
    }
}

getAllPermutations（newItem）；
函数getAllPermutations（项）{
var置换=[]；
getAllPermutations0（项，排列，[]）；
控制台日志（排列）；
}
函数getAllPermutations0（项、置换、数组）{
if（array&&array.length==item.Settings.length）{
permutations.push（array.slice（））；//切片克隆数组
返回；
}
var指数=数组长度；
变量设置=项目设置[索引]；
对于（变量i=0；i

这里是一个非递归解决方案。它接受一个空的或现有的

设置

“矩阵”和一个

值

数组，并返回一个新矩阵，作为为每个新值克隆的现有矩阵内容的组合，附加成对的新值设置项

[A]

->

[1,2]

给出了

[A][1][A][2]

[A][1][A][2]

->

[X，Y]

给出了

[A][1][X][A][2][Y][A][2][X][A][1][Y]

等等

function processSettings(settings, name, values) {
  if (settings.length == 0) {
    values.forEach(function(value) {
      settings.push( [{ SettingName: name, value: value }] )
    })
  } else {
    var oldSettings = JSON.parse(JSON.stringify(settings)), settings = [], temp, i = 0
    for (i; i<values.length; i++) {
      temp = JSON.parse(JSON.stringify(oldSettings))
      temp.forEach(function(setting) {
        setting.push( { SettingName: name, value: values[i] } )
        settings.push(setting)
      })
     }
   }
   return settings
}

---

您可以使用

Array.prototype.map（）

，

for

循环，

while

循环，

Array.prototype.concat（）

。迭代

gender

值；从索引

0

开始依次选择

color

，

size

值；从当前

性别

迭代最远相邻数组，增加最近相邻数组的索引；合并生成的两个

性别

数组，形成一个包含

性别

、

颜色

、

大小

var colors = newItem.Settings[0].values;
var sizes = newItem.Settings[1].values;
var gen = newItem.Settings[2].values;
var i = sizes.length;

var res = [].concat.apply([], gen.map(function(value, key) {
  var next = -1;
  var arr = [];
  for (var curr = 0; curr < i; curr++) {
    while (next < i - 1) {
      arr.push([{
        SettingName: "gender",
        value: value
      }, {
        SettingName: "size",
        value: sizes[curr]
      }, {
        SettingName: "color",
        value: colors[++next]
      }])
    }
    next = -1;
  }
  return arr
}))

var colors=newItem.Settings[0]。值；
变量大小=newItem.Settings[1]。值；
var gen=newItem.Settings[2]。值；
var i=尺寸。长度；
var res=[].concat.apply（[]，gen.map（函数（值，键）{
var-next=-1；
var-arr=[]；
对于（var curr=0；curr

var newItem={
“名称”：“新项目”，
“设置”：[{
“名称”：“颜色”，
“价值观”：[
“绿色”，
“蓝色”，
“红色”
]
}, {
“名称”：“大小”，
“价值观”：[
"15",
"18",
"22"
]
}, {
“姓名”：“性别”，
“价值观”：[
“男性”，
“女性”
]
}]
}
var colors=newItem.Settings[0]。值；
变量大小=newItem.Settings[1]。值；
var gen=newItem.Settings[2]。值；
var i=尺寸。长度；
var res=[].concat.apply（[]，gen.map（函数（值，键）{
var-next=-1；
var-arr=[]；
对于（var curr=0；curr

---

使用

数组.prototype.reduce（）

，

数组.prototype.sort（）

，

对象.keys（）

，

for

循环，

while

循环的方法

var newItem={
名称：'新项目'，
设置：[
{
名称：'颜色'，
值：[“绿色”、“蓝色”、“红色”]
}, 
{
名称：'大小'，
值：['15'，'18'，'22']
}, 
{
姓名：'性别'，
值：[“男性”、“女性”]
}
]
};
var props=[“设置名称”，“值”]；
var settings=newItem.settings；
功能p（设置、道具）{
var数据=设置.reduce（函数（res、设置、索引）{
var name=setting.name；
var obj={}；
obj[name]=设置值；
res.push（obj）；
返回res.length
这很好，但我更喜欢另一个答案，因为它没有使用JSON.parse（JSON.stringify（settings）），但在经过测量之后，我发现这种方法的速度快了3倍（可能只是JSbin vs JSfiddle）嘿@CMS，我想不是-脚本是在你的浏览器中执行的…我不知道，关于
JSON.parse（JSON.stringify（settings））
速度极其缓慢的神话，可能是h
[
[{"SettingName":"color","value":"green"},{"SettingName":"size","value":"15"},{"SettingName":"gender","value":"male"}],
[{"SettingName":"color","value":"blue"},{"SettingName":"size","value":"15"},{"SettingName":"gender","value":"male"}],
[{"SettingName":"color","value":"red"},{"SettingName":"size","value":"15"},{"SettingName":"gender","value":"male"}],
[{"SettingName":"color","value":"green"},{"SettingName":"size","value":"18"},{"SettingName":"gender","value":"male"}],
[{"SettingName":"color","value":"blue"},{"SettingName":"size","value":"18"},{"SettingName":"gender","value":"male"}],
[{"SettingName":"color","value":"red"},{"SettingName":"size","value":"18"},{"SettingName":"gender","value":"male"}],
[{"SettingName":"color","value":"green"},{"SettingName":"size","value":"22"},{"SettingName":"gender","value":"male"}],
[{"SettingName":"color","value":"blue"},{"SettingName":"size","value":"22"},{"SettingName":"gender","value":"male"}],
[{"SettingName":"color","value":"red"},{"SettingName":"size","value":"22"},{"SettingName":"gender","value":"male"}],
[{"SettingName":"color","value":"green"},{"SettingName":"size","value":"15"},{"SettingName":"gender","value":"female"}],
[{"SettingName":"color","value":"blue"},{"SettingName":"size","value":"15"},{"SettingName":"gender","value":"female"}],
[{"SettingName":"color","value":"red"},{"SettingName":"size","value":"15"},{"SettingName":"gender","value":"female"}],
[{"SettingName":"color","value":"green"},{"SettingName":"size","value":"18"},{"SettingName":"gender","value":"female"}],
[{"SettingName":"color","value":"blue"},{"SettingName":"size","value":"18"},{"SettingName":"gender","value":"female"}],
[{"SettingName":"color","value":"red"},{"SettingName":"size","value":"18"},{"SettingName":"gender","value":"female"}],
[{"SettingName":"color","value":"green"},{"SettingName":"size","value":"22"},{"SettingName":"gender","value":"female"}],
[{"SettingName":"color","value":"blue"},{"SettingName":"size","value":"22"},{"SettingName":"gender","value":"female"}],
[{"SettingName":"color","value":"red"},{"SettingName":"size","value":"22"},{"SettingName":"gender","value":"female"}]
]

var colors = newItem.Settings[0].values;
var sizes = newItem.Settings[1].values;
var gen = newItem.Settings[2].values;
var i = sizes.length;

var res = [].concat.apply([], gen.map(function(value, key) {
  var next = -1;
  var arr = [];
  for (var curr = 0; curr < i; curr++) {
    while (next < i - 1) {
      arr.push([{
        SettingName: "gender",
        value: value
      }, {
        SettingName: "size",
        value: sizes[curr]
      }, {
        SettingName: "color",
        value: colors[++next]
      }])
    }
    next = -1;
  }
  return arr
}))