2017-07-06 106 views
0

我该如何在JavaScript中做这样的事情?从属javascript对象属性

obj = { 
    prop1 = 0; 
    prop2 = 0; 
    prop3 = prop1 + prop2; 
} 

因此,当obj.prop1被更新时,obj.prop3会自动更新。

+0

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_Objects# Defining_getters_and_setters – Bergi

回答

7

尽量让prop3的getter/setter,见例如

var obj = { 
 
    prop1: 1, 
 
    prop2: 4, 
 
    get prop3() { 
 
     return this.prop1 + this.prop2; 
 
    } 
 
}; 
 

 
console.log(obj.prop3); 
 
obj.prop1 = 6; 
 
console.log(obj.prop3);