Embeer.js ArrayProxy findBy()用法及代碼示例

Ember.js 是一個開源 JavaScript 框架，用於開發基於 Model-View-Controller (MVC) 架構的大型客戶端 Web 應用程序。 Ember.js是使用最廣泛的前端應用框架之一。它的目的是加速開發並提高生產力。目前，它被大量網站使用，包括 Square、Discourse、Groupon、Linked In、Live Nation、Twitch 和 Chipotle。

findBy() 方法用於獲取列表中與傳遞的值匹配的第一個值。

用法:

findBy( key, value );

參數：

key: 它是我們想要其值的屬性的名稱。
value: 它是我們要測試其值的鍵的值。

返回值：其他找到的項目返回‘undefined’。

第 1 步：要運行以下示例，您需要有一個 ember 項目。要創建一個，您需要先安裝ember-cli。在終端中寫入以下代碼：

npm install ember-cli

現在您可以通過輸入以下代碼來創建項目：

ember new <project-name> --lang en

步驟 2：要啟動服務器，請鍵入：

ember serve

示例 1：鍵入以下代碼以生成本示例的路由：

ember generate route findBy1

應用程序/路線/findBy1.js


import Route from '@ember/routing/route'; 
import { findBy } from '@ember/array'; 
  
export default class FruitsRoute extends Route { 
    item1 = [ 
        { 
            name: 'Apple', 
            isFruit: true, 
            color: 'red', 
        }, 
        { 
            name: 'Grapes', 
            isFruit: true, 
            color: 'green', 
        }, 
        { 
            name: 'Mango', 
            isFruit: true, 
            color: 'yellow', 
        }, 
        { 
            name: 'Watermelon', 
            isFruit: true, 
            color: 'red', 
        }, 
        { 
            name: 'Orange', 
            isFruit: true, 
            color: 'orange', 
        } 
    ]; 
    item2 = [ 
        { 
            name: 'Lady Finger', 
            isFruit: false, 
            color: 'green', 
        }, 
        { 
            name: 'Brinjal', 
            isFruit: false, 
            color: 'purple', 
        }, 
        { 
            name: 'Potato', 
            isFruit: false, 
            color: 'brown', 
        }, 
        { 
            name: 'Onion', 
            isFruit: false, 
            color: 'violer', 
        }, 
    ]; 
    model() { 
        return this.item1; 
    } 
    setupController(controller, model) { 
        super.setupController(controller, model); 
        controller.set('item1', this.item1); 
        controller.set('item2', this.item2); 
    } 
}

應用程序/控製器/findBy1.js


import Ember from 'ember'; 
import { removeAt, unshiftObjects, objectAt,  
    uniqBy, find } from '@ember/array'; 
  
export default Ember.Controller.extend({ 
    actions: { 
        Find_item(data) { 
            let foo = this.item1.findBy('name', data); 
            alert(foo ? `${foo.name} present in list` :  
                'No items not present in list'); 
        }, 
        AddItems() { 
            this.item1.addObjects(this.item2); 
        } 
  
    }, 
});

應用程序/模板/findBy1.hbs


{{page-title "findBy"}} 
<h2>List of Item </h2> 
<table> 
    <tr> 
          <th>Name</th> 
        <th>Fruit</th> 
        <th>Color</th> 
      </tr> 
      {{#each @model as |Eatable|}} 
    <tr> 
          <td>{{Eatable.name}}</td> 
          <td>{{Eatable.isFruit}}</td> 
          <td>{{Eatable.color}}</td> 
    </tr> 
      {{/each}} 
</table> 
<br /> 
<div> 
    <label>Enter Quantity: </label> 
      {{input value=this.temp}} 
</div> 
<input 
    type="button"
      id="greet"
      value="Find Item"
      {{action "Find_item" this.temp}} 
/> 
<br /><br /> 
<br /><br /> 
<input type="button" id="add-items" 
    value="Add Items" {{action "AddItems"}} /> 
{{outlet}}

輸出：訪問 localhost:4200/findBy1 查看輸出

Ember.js ArrayProxy findBy 方法

示例 2：鍵入以下代碼以生成本示例的路由：

ember generate route findBy2

應用程序/路線/findBy2.js


import Route from '@ember/routing/route'; 
  
class student { 
    name = null; 
    gender = null; 
    clas = null; 
    grade = null; 
    constructor(name, gender, clas, grade) { 
        this.name = name; 
        this.gender = gender; 
        this.clas = clas; 
        this.grade = grade; 
    } 
} 
  
export default class StudentsRoute extends Route { 
    students = [ 
        new student('Aakash', 'M', 10, 'P'), 
        new student('Soniya', 'F', 8, 'F'), 
        new student('Esnoor', 'M', 9, 'P'), 
        new student('Isha', 'F', 11, 'P'), 
        new student('Doman', 'M', 12, 'F'), 
        new student('Lolu', 'M', 10, 'P'), 
        new student('Satyam', 'M', 10, 'F'), 
    ]; 
    temp1 = ['name', 'gender', 'class', 'grade']; 
    temp2; 
    model() { 
        return this.students; 
    } 
    setupController(controller, model) { 
        super.setupController(controller, model); 
        controller.set('students', this.students); 
        controller.set('temp', this.temp); 
        controller.set('temp1', this.temp1); 
        controller.set('temp2', this.temp2); 
    } 
}

應用程序/控製器/findBy2.js


import Ember from 'ember'; 
import { mapBy, every } from '@ember/array'; 
  
export default Ember.Controller.extend({ 
    actions: { 
        setattr(temp) { 
            this.set('temp', temp); 
        }, 
        find_Data(data, data1) { 
            [data, data1] = data == 'class' ?  
                ['clas', JSON.parse(data1)] : [data, data1]; 
            let foo = this.students.findBy(data, data1); 
            alert(foo ? `${foo.name} is from class ${foo.clas}` 
                : `No One present`); 
        }, 
    }, 
});

應用程序/模板/findBy2.hbs


{{page-title "Student"}} 
<h3>List of Students: </h3> 
<br /><br /> 
<table> 
    <tr> 
        <th>Name</th> 
        <th>Gender </th> 
        <th>Class </th> 
        <th>Grade </th> 
      </tr> 
      {{#each @model as |detail|}} 
    <tr> 
          <td>{{detail.name}}</td> 
          <td> {{detail.gender}}</td> 
          <td>{{detail.clas}}</td> 
          <td>{{detail.grade}}</td> 
    </tr> 
      {{/each}} 
</table> 
<br /> 
<div> 
    <label>Select Attribute: </label> 
      <select onchange={{action "setattr" 
        value="target.value"}}> 
    {{#each this.temp1 as |attribute|}} 
          <option value={{attribute}}>{{attribute}}</option> 
    {{/each}} 
      </select> 
</div> 
<br /> 
<div> 
    <label>Enter value for Attribute: </label> 
      {{input value=this.temp2}} 
</div> 
<div> 
    <input 
        type="button"
        id="check-student"
        value="Get the First Student"
        {{action "find_Data" this.temp this.temp2}} 
      /> 
</div> 
{{outlet}}

輸出：訪問 localhost:4200/findBy2 查看輸出

Ember.js ProxyArray findBy 方法

參考：https://api.emberjs.com/ember/2.14/classes/Ember.Array/methods/findBy?anchor=findBy

相關用法

注：本文由純淨天空篩選整理自jeemains0neet大神的英文原創作品 Ember.js ArrayProxy findBy() Method。非經特殊聲明，原始代碼版權歸原作者所有，本譯文未經允許或授權，請勿轉載或複製。