如何获取 javascript 对象属性的子集？

为了获取 JavaScript 对象的属性子集，我们使用解构和属性简写。解构赋值语法是一种 JavaScript 表达式，它可以将数组中的值或对象中的属性解包到不同的变量中。
句法：

subset = (({a, c}) => ({a, c}))(obj);

示例 1：使用解构赋值获取 javascript 对象属性的子集。

html

 

    
      Get a subset of a javascript object’s properties
  

 

    
        
          GeeksforGeeks
      
        
          Get a subset of a javascript object’s properties
      
        
            obj = {
                property1: 5,
                property2: 6,
                property3: 7
            };
            subset = (({
                property1, property3
            }) => ({
                property1, property3
            }))(obj);
 
            var output = 'Subset Object: <br>';
            for (var property in subset) {
                output += property + ': ' + subset[property] + ';<br>';
            }
            document.write(output);
        
    

 

输出：

在ES6中，有一种非常简洁的方法可以使用析构来做到这一点。破坏使您可以轻松地添加到对象并制作子集对象。
句法：

const {c, d, ...partialObject} = object;
const subset = {c, d};

示例 2：使用解构赋值获取 javascript 对象属性的子集。

html

 

    
      Get a subset of a javascript object’s properties
  

 

    
        
          GeeksforGeeks
      
        
          Get a subset of a javascript object’s properties
      
        
            const object = {
                property1: 'a',
                property2: 'b',
                property3: 'c',
                property4: 'd',
            }
 
            const {
                property1,
                property4,
                ...pObject
            }
 
            = object;
            const subset = {
                property1,
                property4
            }
 
            ;
            var output = 'Subset Object: <br>';
            for (var property in subset) {
                output += property + ': ' +
                    subset[property] + ';<br>';
            }
 
            document.write(output);
        
    

 

输出：