javascript - jQuery extent JSON数组参数替换

Question

我正在尝试了解 jquery 扩展方法，根据 API documentation

The merge performed by $.extend() is not recursive by default; if a property of the first object is itself an object or array, it will be completely overwritten by a property with the same key in the second or subsequent object. The values are not merged.

它说数组或对象属性将不会合并并将被替换。在下面的示例中，参数是 JSON 数组，它正在合并而不是被替换。

var a = {
    external : true,
    parameter : [{name:'ip1'},{name:'ip2'},{name:'ip3'}]

};
var b = {
    data:'Sumeet',
    parameter : [{name:'ip1'},{name:'ip2'}]
};


$.extend(true,a,b);

console.log(a);

Output : 


{
  data: "Sumeet",
  external: true,
  parameter: [{
     name: "ip1"
  }, {
    name: "ip2"
  }, {
    name: "ip3"
 }]
}

参数应该只有ip1和ip2

Answer 1

请注意，您的引用说“默认”。后面的文档还说:

However, by passing true for the first function argument, objects will be recursively merged.

全段:

The merge performed by $.extend() is not recursive by default; if a property of the first object is itself an object or array, it will be completely overwritten by a property with the same key in the second or subsequent object. The values are not merged. This can be seen in the example below by examining the value of banana. However, by passing true for the first function argument, objects will be recursively merged.