Ember.js ArrayProxy rejectBy() Method

Ember.js is an open-source JavaScript framework used for developing large client-side web applications which is based on Model-View-Controller (MVC) architecture. Ember.js is one of the most widely used front-end application frameworks. It is made to speed up development and increase productivity. Currently, it is utilized by a large number of websites, including Square, Discourse, Groupon, Linked In, Live Nation, Twitch, and Chipotle.

The rejectBy() method is used to get the array of items that do not return truthy values for the provided key.

Syntax:

reject( key, value );

Parameters:

• key: It is the name of the key whose value we want to check.
• value: It is the value to check against the key.

Return Value: A rejected Array.

Steps to Install and Run Ember.js:

Step 1: To run the following examples you will need to have an ember project with you. To create one, you will need to install ember-cli first. Write the below code in the terminal:

npm install ember-cli

Step 2: Now you can create the project by typing in the following piece of code:

ember new <project-name> --lang en

To start the server, type:

ember serve

Example 1: Type the following code to generate the route for this example:

ember generate route rejectBy1

app/routes/rejectBy1.js

import Route from "@ember/routing/route";

export default class StudentsRoute extends Route {
    students = [
        {
            name: "Aaush Somankar",
            gender: "M",
            class: 12,
            grade: "A",
            mobile: 7897391833,
        },
        {
            name: "Aman Prakash",
            gender: "M",
            class: 10,
            grade: "A",
            mobile: 8293839918,
        },
        {
            name: "Siya guru",
            gender: "F",
            class: 11,
            grade: "B",
            mobile: 6293839912,
        },
        {
            name: "Ramesh verma",
            gender: "M",
            class: 10,
            grade: "A",
            mobile: 7193839932,
        },
        {
            name: "Esnoor",
            gender: "M",
            class: 9,
            grade: "F",
            mobile: 8372819383,
        },
        {
            name: "Balit",
            gender: "M",
            class: 10,
            grade: "A",
            mobile: 7361927365,
        },
        {
            name: "Dora",
            gender: "F",
            class: 12,
            grade: "F",
            mobile: 5634152617,
        },
        {
            name: "Lalu",
            gender: "F",
            class: 8,
            grade: "A",
            mobile: 8372618392,
        },
        {
            name: "Pokhraj",
            gender: "M",
            class: 11,
            grade: "F",
            mobile: 9302810231,
        },
        {
            name: "Rahul",
            gender: "M",
            class: 9,
            grade: "A",
            mobile: 7837919373,

        },
        {
            name: "Ram",
            gender: "M",
            class: 12,
            grade: "A",
            mobile: 8272112539,
        },
        {
            name: "Priti",
            gender: "F",
            class: 9,
            grade: "F",
            mobile: 8836172912,
        },
        {
            name: "Sita",
            gender: "F",
            class: 8,
            grade: "A",
            mobile: 9193830293,
        },
    ];
    convert(string) {
        this.item = string.split(",").map((item) => item.trim());
        return this.item;
    }

    model() {
        return this.students;
    }
    setupController(controller, model) {
        super.setupController(controller, model);
        controller.set("students", this.students);
        controller.set("convert", this.convert);
        controller.set("item", this.item);
    }
}

app/controllers/rejectBy1.js

import Ember from "ember";

export default Ember.Controller.extend({
    actions: {
        select() {
            let temp = this.students.uniqBy('class');
            let ans = temp.mapBy('name')
            alert(ans.join('\n'))
        },
        hide() {
            this.students.setEach('mobile', '**********')
        },
        allPass() {
            let tempItems = this.students.rejectBy('grade', 'F');
            let ans = tempItems.mapBy('name')
            alert(ans.join('\n'))

        },
        remove() {
            this.students.shiftObject();
        },
        check_item(idx) {
            let temp = this.students.objectAt(JSON.parse(idx));
            alert(temp.name)
        },
        check_items(idx1, idx2) {
            let temp = this.students.slice(idx1, idx2);
            let ans = temp.mapBy('name')
            alert(ans.join('\n'))
        },

    },
});

app/templates/rejectBy1.hbs

{{page-title "rejectBy"}}
<h3>List of Students: </h3>

<table>
    <tr>
        <th>Name</th>
        <th>Class</th>
        <th>Gender</th>
        <th>Grade</th>
        <th>Mobile No.</th>
    </tr>
    {{#each @model as |student|}}
    <tr>
        <td>{{student.name}}</td>
        <td>{{student.class}}</td>
        <td>{{student.gender}}</td>
        <td>{{student.grade}}</td>
        <td>{{student.mobile}}</td>
    </tr>
    {{/each}}
</table>
<br /><br />
<div>
    <label>Enter first index: </label>
    {{input value=this.temp}}
</div>
<div>
    <label>Enter last indexs: </label>
    {{input value=this.temp2}}
</div>
<input
    type="button"
    id="check-atIndex"
    value="Slice list"
    {{action "check_items" this.temp this.temp2}}
/>
<br /><br />
<input
    type="button"
    id="remove-last"
    value="Remove First Student"
    {{action "remove"}}
/>
<br /><br />
<input
    type="button"
    id="hide-number"
    value="Hide Mobile Numbers"
    {{action "hide"}}
/>
<br /><br />
<input
    type="button"
    id="all-pass"
    value="Show All Passed Stuedents"
    {{action "allPass"}}
/>

<br /><br />
<input
    type="button"
    id="select-student"
    value="Select One Student Of Each class"
    {{action "select"}}
/>
{{outlet}}

Output: Visit localhost:4200/rejectBy1 to view the output

Ember.js ArrayProxy rejectBy method

Example 2: Type the following code to generate the route for this example:

ember generate route rejectBy2

app/routes/rejectBy2.js

import Route from '@ember/routing/route';
export default class FruitsRoute extends Route {
    fruits = [
        {
            'name': 'Lady Finger',
            'isFruit': false,
            'color': 'green',
            'quant': 2,
        },
        {
            'name': 'Brinjal',
            'isFruit': false,
            'color': 'purple',
            'quant': 2,
        },
        {
            'name': 'Apple',
            'isFruit': true,
            'color': 'red',
            'quant': 5,
        },
        {
            'name': 'Grapes',
            'isFruit': true,
            'color': 'green',
            'quant': 4,
        },
        {
            'name': 'Mango',
            'isFruit': true,
            'color': 'yellow',
            'quant': 3,
        },
        {
            'name': 'Watermelon',
            'isFruit': true,
            'color': 'red',
            'quant': 2,
        },
        {
            'name': 'Orange',
            'isFruit': true,
            'color': 'orange',
            'quant': 2,
        },
        {
            'name': 'Banana',
            'isFruit': true,
            'color': 'yellow',
            'quant': 5,
        },
        {
            'name': 'Papaya',
            'isFruit': true,
            'color': 'orange',
            'quant': 5,
        },
    ];
    item2;
    item3;
    model(){
        return this.fruits;
    }
    setupController(controller,model) {
        super.setupController(controller, model);
        controller.set('fruits', this.fruits);
        controller.set('item1', this.item1);
        controller.set('item2', this.item2);
        controller.set('item3', this.item3);
    }
}

app/controllers/rejectBy2.js

import Ember from "ember";

export default Ember.Controller.extend({
actions: {
    show_Fruits( ) {
        let temp = this.fruits.rejectBy('isFruit',false);
        let foo = temp.mapBy('name');
        alert(foo.join('\n'))
    },
    slice_items( idx1, idx2) {
        let foo = this.fruits.slice(idx1, idx2);
        let ans = foo.mapBy('name')
        alert(ans.join('\n'))
    },
    remove() {
        this.fruits.shiftObject( );

    },
    set_quant(data) {
        this.fruits.setEach('quant', data );

    },
    select(){
        let temp = this.fruits.uniqBy('color');
        let ans = temp.mapBy('name');
        alert(ans.join('\n'));
    }
},
});

app/templates/rejectBy2.hbs

{{page-title "rejectBy"}}
<h3>Here is a list of eatables: </h3>
<table>
    <tr>
        <th>Name</th>
        <th>Fruit</th>
        <th>Color</th>
        <th>Quantity</th>
    </tr>
    {{#each @model as |detail|}}
    <tr>
        <td>{{detail.name}}</td>
        <td>{{detail.isFruit}}</td>
        <td>{{detail.color}}</td>
        <td>{{detail.quant}}</td>
    </tr>
    {{/each}}
</table>
<br /><br />
<div>
    <label>Enter first index: </label>
    {{input value=this.temp}}
</div>
<div>
    <label>Enter last indexs: </label>
    {{input value=this.temp2}}
</div>
<input type="button"
        id="check-atIndex"
        value="Slice list"
        {{action "slice_items" this.temp this.temp2}}
/>
<br/>
<br/>
<div>
    <label>Enter Quantity: </label>
    {{input value=this.temp3}}
</div>
<input
    type="button"
    id="set-quant"
    value="Set Each Quantity"
    {{action "set_quant" this.temp3}}
/>
<br/><br/>
<div>
    <input type="button"
        id="removeFruit"
        value="Remove 1's Fruit"
        {{action "remove" }}    >
</div>
<br/>
<div>
    <input type="button"
        id="addFruit"
        value="Show Fruit"
        {{action "show_Fruits"}}    >
</div>
<br/>
<input
    type="button"
        id="select-fruits"
        value="Select One item of Each color"
        {{action "select"}}
/>
{{outlet}}

Output: Visit localhost:4200/rejectBy2 to view the output

Ember.js ArrayProxy reject Method

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