如何从属性值生成变化

Question

我必须制作一个具有属性值的所有组合的数组。

属性/值对象：

let attributes = { 
    color: ['red', 'green', 'blue'], 
    sizes: ['sm', 'md', 'lg'], 
    material: ['cotton', 'wool'] 
} 

我需要使所有可能的组合作为这样的阵列。

color sizes  material 
red  sm  cotton 
red  sm  wool 
red  md  cotton 
red  md  wool 
red  lg  cotton 
red  lg  wool 
blue  sm  cotton 
blue  sm  wool 
blue  md  cotton 
blue  md  wool 
blue  lg  cotton 
blue  lg  wool 
green sm  cotton 
green sm  wool 
green md  cotton 
green md  wool 
green lg  cotton 
green lg  wool 

属性类型和值计数都是不确定的（至少为1）。我怎样才能做到这一点？

这是我迄今为止

// keys = ['color', 'sizes', 'material'] 
// attributes is the same as above. 

for (let keysIndex = 0; keysIndex < keys.length; keysIndex++) { 
    let key = keys[i]; 
    let values = attributes[key]; 

    //loop through each value 
    for (let valuesIndex = 0; valuesIndex < values.length; valuesIndex++) { 

     // for each value, loop through all keys 
     for (let keysIndex2 = 0; keysIndex2 < keys.length; keysIndex2++) { 
      if (keysIndex === keysIndex2) { 
       continue; 
      } 

      for (let valuesIndex2 = 0; valuesIndex2 < values.length; valuesIndex2++) { 

       // What do I do from here? 
       // Not sure if this is even the right path? 

      } 

     } 

    } 

} 

Answer 1

我采取了两个步骤的方法的代码...第一I从attributes对象提取只是数组的数组（[['red', 'green', 'blue'], ['sm', ...], ...]）。然后我递归地计算这些数组的产品。然后，我用适当的键将它们放回物体中。

let attributes = { 
    color: ['red', 'green', 'blue'], 
    sizes: ['sm', 'md', 'lg'], 
    material: ['cotton', 'wool'] 
}; 

let getProducts = (arrays) => { 
    if (arrays.length === 0) { 
     return [[]]; 
    } 

    let results = []; 

    getProducts(arrays.slice(1)).forEach((product) => { 
     arrays[0].forEach((value) => { 
      results.push([value].concat(product)); 
     }); 
    }); 

    return results; 
}; 

let getAllCombinations = (attributes) => { 
    let attributeNames = Object.keys(attributes); 

    let attributeValues = attributeNames.map((name) => attributes[name]); 

    return getProducts(attributeValues).map((product) => { 
     obj = {}; 
     attributeNames.forEach((name, i) => { 
      obj[name] = product[i]; 
     }); 
     return obj; 
    }); 
}; 

console.log(getAllCombinations(attributes)); 

// Output: 
// [ { color: 'red', sizes: 'sm', material: 'cotton' }, 
// { color: 'green', sizes: 'sm', material: 'cotton' }, 
// { color: 'blue', sizes: 'sm', material: 'cotton' }, 
// { color: 'red', sizes: 'md', material: 'cotton' }, 
// { color: 'green', sizes: 'md', material: 'cotton' }, 
// { color: 'blue', sizes: 'md', material: 'cotton' }, 
// { color: 'red', sizes: 'lg', material: 'cotton' }, 
// { color: 'green', sizes: 'lg', material: 'cotton' }, 
// { color: 'blue', sizes: 'lg', material: 'cotton' }, 
// { color: 'red', sizes: 'sm', material: 'wool' }, 
// { color: 'green', sizes: 'sm', material: 'wool' }, 
// { color: 'blue', sizes: 'sm', material: 'wool' }, 
// { color: 'red', sizes: 'md', material: 'wool' }, 
// { color: 'green', sizes: 'md', material: 'wool' }, 
// { color: 'blue', sizes: 'md', material: 'wool' }, 
// { color: 'red', sizes: 'lg', material: 'wool' }, 
// { color: 'green', sizes: 'lg', material: 'wool' }, 
// { color: 'blue', sizes: 'lg', material: 'wool' } ]