Confirm whether an angular2 input checkbox has been checked or not

Question

Confirm whether an angular2 input checkbox has been checked or not

I have implemented a table in my HTML with an input checkbox present in each row.

Currently, I am attempting to determine whether the checkbox has been selected or not. Below is the approach I have taken:

HTML:

<table class="table table-hover" id="just_a_table">
    <thead>
        <tr>
          <th scope="col">Select</th>
          <th scope="col">IP Addr</th>
        </tr>
    </thead>
    <tbody>
        <tr *ngFor="let data of instances">
          <td><input type="checkbox" (click)='onSelect()'></td>
          <td>{{data["IP"]}}</td>
        </tr>
    </tbody>
</table>

TS:

onSelect() {
    // Get table data from the html and check if the checkbox is active.
    // Access rows of the table using "rows" object and cells using "cells" object.
    this.table_data = document.getElementById("just_a_table")

        for (var i=1, row; row = this.table_data.rows[i]){
          for (var j=0, cell; cell = row.cells[j]){
            if (<HTMLInputElement>cell[1].checked){
              console.log("It is checked")
            }
        }
    }
}

I decided to take this method as I prefer not to target the input element by its ID to check its status.

If you have any suggestions or guidance on how I can achieve this more efficiently, it would be greatly appreciated.

angular typescript

Answer 1

Answer №1

Customized HTML Code

 <table id="custom_table" class="custom-table">
       <thead>
           <tr>
               <th scope="col">Selection</th>
               <th scope="col">IP Address</th>
           </tr>
        </thead>
        <tbody>
           <tr *ngFor="let data of instances">
               <td><input type="checkbox" (change)='onSelect($event)'></td>
               <td>{{data["IP"]}}</td>
           </tr>
        </tbody>
   </table>

To resolve the issue, remember to utilize event.target.checked. Here's how you can implement it:

Updated TypeScript Function

onSelect(event) {
     if ( event.target.checked ) {
        // Add your logic here
    }
}

Ensure to use (change) over (click) for better practice
Avoid reliance on vanilla JS when using Typescript and Angular, as these frameworks enhance development efficiency

Answer 2

Customized HTML Code

 <table id="custom_table" class="custom-table">
       <thead>
           <tr>
               <th scope="col">Selection</th>
               <th scope="col">IP Address</th>
           </tr>
        </thead>
        <tbody>
           <tr *ngFor="let data of instances">
               <td><input type="checkbox" (change)='onSelect($event)'></td>
               <td>{{data["IP"]}}</td>
           </tr>
        </tbody>
   </table>

To resolve the issue, remember to utilize event.target.checked. Here's how you can implement it:

Updated TypeScript Function

onSelect(event) {
     if ( event.target.checked ) {
        // Add your logic here
    }
}

Ensure to use (change) over (click) for better practice
Avoid reliance on vanilla JS when using Typescript and Angular, as these frameworks enhance development efficiency

Answer 3

Answer №2

To begin, I recommend utilizing the Angular (click) event binding and adjusting your ngFor loop as follows:

<tr *ngFor="let data of instances; let i = index" [attr.data-index]="i">

This modification allows us to easily identify which checkbox is selected.

<table class="table table-hover" id="just_a_table">
    <thead>
        <tr>
          <th scope="col">Select</th>
          <th scope="col">IP Addr</th>
        </tr>
    </thead>
    <tbody>
        <tr *ngFor="let data of instances; let i = index" [attr.data-index]="i">
          <td><input type="checkbox" value="false" (click)='onSelect($event, i)'></td>
        </tr>
    </tbody>
</table>

Next, initializing an array with false values matching the length of instances would be beneficial if you require knowledge of the checked checkboxes. While there are alternative approaches, this one is straightforward.

constructor() {
    for (let i = 0; i < this.instances.length; i++) {
        this.resultArray.push(false);
    }
}

Utilize event.target.checked to determine the checked status of the clicked checkbox. Then, based on the index, update the corresponding array element. Ensure to include the parameters in the function definition as well.

onSelect(event, index) {
    // If checking which checkboxes are selected is necessary
    this.resultArray[index] = event.target.checked;
    // If not required
    const result: EventTarget = event.target.checked;
    // Perform appropriate actions with the value
}

Answer 4

To begin, I recommend utilizing the Angular (click) event binding and adjusting your ngFor loop as follows:

<tr *ngFor="let data of instances; let i = index" [attr.data-index]="i">

This modification allows us to easily identify which checkbox is selected.

<table class="table table-hover" id="just_a_table">
    <thead>
        <tr>
          <th scope="col">Select</th>
          <th scope="col">IP Addr</th>
        </tr>
    </thead>
    <tbody>
        <tr *ngFor="let data of instances; let i = index" [attr.data-index]="i">
          <td><input type="checkbox" value="false" (click)='onSelect($event, i)'></td>
        </tr>
    </tbody>
</table>

Next, initializing an array with false values matching the length of instances would be beneficial if you require knowledge of the checked checkboxes. While there are alternative approaches, this one is straightforward.

constructor() {
    for (let i = 0; i < this.instances.length; i++) {
        this.resultArray.push(false);
    }
}

Utilize event.target.checked to determine the checked status of the clicked checkbox. Then, based on the index, update the corresponding array element. Ensure to include the parameters in the function definition as well.

onSelect(event, index) {
    // If checking which checkboxes are selected is necessary
    this.resultArray[index] = event.target.checked;
    // If not required
    const result: EventTarget = event.target.checked;
    // Perform appropriate actions with the value
}

Answer 5

Answer №3

<div *ngFor="let item of data">
   <p><input type="checkbox" (click)='toggleSelection($event)'></p>
   <p>{{item["name"]}}</p>
</div>


toggleSelection(event) {
    if (event.target.checked) {
       // add your logic here.
        console.log('checked', event.target.checked);
       }

Hope this solution works for you!! :)

Answer 6

<div *ngFor="let item of data">
   <p><input type="checkbox" (click)='toggleSelection($event)'></p>
   <p>{{item["name"]}}</p>
</div>


toggleSelection(event) {
    if (event.target.checked) {
       // add your logic here.
        console.log('checked', event.target.checked);
       }

Hope this solution works for you!! :)

Answer 7

Answer №4

function checkSelectedCells() {
    let table = document.getElementById("just_a_table");
    for (let i = 1; i < table.rows.length; i++){
        for (let j = 0; j < table.rows[i].cells.length; j++){
            if (table.rows[i].cells[j].children[0].checked){
                console.log("This cell is checked");
            }
        }
    }
}

Answer 8

function checkSelectedCells() {
    let table = document.getElementById("just_a_table");
    for (let i = 1; i < table.rows.length; i++){
        for (let j = 0; j < table.rows[i].cells.length; j++){
            if (table.rows[i].cells[j].children[0].checked){
                console.log("This cell is checked");
            }
        }
    }
}

Answer 9

Answer №5

***************************************************************

Give this a try:

Declare a Boolean variable called checkBoxValidate

Initialize the variable to false in the ngOnInit() method: this.checkBoxValidate = false;

<table class="table table-hover" id="just_a_table">
    <thead>
        <tr>
            <th scope="col">Select</th>
            <th scope="col">IP Addr</th>
        </tr>
    </thead>
    <tbody>
        <tr *ngFor="let data of instances">
            <td><input type="checkbox" (click)='onSelect()'></td>
            <td>{{data["IP"]}}</td>
        </tr>
    </tbody>

TypeScript

onSelect()
{
    if(this.checkBoxValidate == false)
    {
        this.checkBoxValidate = true;
    }
    else
    { 
        this.checkBoxValidate = false;
    }
}

If checkBoxValidate is true, checkbox is checked, otherwise it is unchecked

***************************************************************

Answer 10

***************************************************************

Give this a try:

Declare a Boolean variable called checkBoxValidate

Initialize the variable to false in the ngOnInit() method: this.checkBoxValidate = false;

<table class="table table-hover" id="just_a_table">
    <thead>
        <tr>
            <th scope="col">Select</th>
            <th scope="col">IP Addr</th>
        </tr>
    </thead>
    <tbody>
        <tr *ngFor="let data of instances">
            <td><input type="checkbox" (click)='onSelect()'></td>
            <td>{{data["IP"]}}</td>
        </tr>
    </tbody>

TypeScript

onSelect()
{
    if(this.checkBoxValidate == false)
    {
        this.checkBoxValidate = true;
    }
    else
    { 
        this.checkBoxValidate = false;
    }
}

If checkBoxValidate is true, checkbox is checked, otherwise it is unchecked

***************************************************************

Answer 11

Answer №6

To implement in angular 2+, follow the example below:

<div class="togglebutton">
                                            <label>
                                                <input type="checkbox" [checked]="record.isStatus" (change)="changeStatus(record.id,$event)">
                                                <span class="toggle"></span>

                                            </label>
                                        </div>

In your TypeScript file:

changeStatus(id, e) {
        var status = e.target.checked;
        this._companyHubService.addOrRemoveStatus(id, status).subscribe(result => {
            this.modalSave.emit();
            if (status)
                this.notify.success(this.l('AddedAsStatus'));
            else
                this.notify.success(this.l('RemovedFromStatus'));

        });
    }

Answer 12

To implement in angular 2+, follow the example below:

<div class="togglebutton">
                                            <label>
                                                <input type="checkbox" [checked]="record.isStatus" (change)="changeStatus(record.id,$event)">
                                                <span class="toggle"></span>

                                            </label>
                                        </div>

In your TypeScript file:

changeStatus(id, e) {
        var status = e.target.checked;
        this._companyHubService.addOrRemoveStatus(id, status).subscribe(result => {
            this.modalSave.emit();
            if (status)
                this.notify.success(this.l('AddedAsStatus'));
            else
                this.notify.success(this.l('RemovedFromStatus'));

        });
    }

Confirm whether an angular2 input checkbox has been checked or not

Answer №1

Answer №2

Answer №3

Answer №4

Answer №5

Answer №6

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