Underscore.JS - where 方法

語法

_.where(list, properties)

where 方法迭代給定的元素列表，對每個元素呼叫謂詞。它返回 properties 中所有匹配的鍵值對。

檢視列表中的每個值，返回一個數組，其中包含所有與 properties 中列出的鍵值對匹配的值。

示例

var _ = require('underscore');

var list = [{"title": "Learn Java", "Author": "Sam", "Cost": 100},
   {"title": "Learn Scala", "Author": "Joe", "Cost": 200},
   {"title": "Learn C", "Author": "Sam", "Cost": 200} ]
   
//Example 1. find books whose author is Sam
var result = _.where(list, { "Author": "Sam" });
console.log(result);

//Example 2. find books whose cost is 200
var result = _.where(list, { "Cost": 200 });
console.log(result);

將以上程式儲存在tester.js中。執行以下命令以執行此程式。

命令

\>node tester.js

輸出

[
  { title: 'Learn Java', Author: 'Sam', Cost: 100 },
  { title: 'Learn C', Author: 'Sam', Cost: 200 }
]
[
  { title: 'Learn Scala', Author: 'Joe', Cost: 200 },
  { title: 'Learn C', Author: 'Sam', Cost: 200 }
]