How to disable a checkbox based on conditions in angular 6?

Question

My html code,

<div>
  <div>
   <input type="checkbox" id="Checkbox0" name="cCheckbox0" class="custom-control-input" (change)="checkSelected(checkBox[0].label)">
   <label class="label" for="Checkbox0" >first</label>
  </div>
  <div>
  <input type="checkbox" id="Checkbox1" name="cCheckbox1" class="custom-control-input" (change)="checkSelected(checkBox[1].label)">
   <label class="label" for="Checkbox1" >first</label>
  </div>
  <div>
  <input type="checkbox" id="Checkbox2" name="cCheckbox2" class="custom-control-input" (change)="checkSelected(checkBox[2].label)">
   <label class="label" for="Checkbox2" >first</label>
  </div>
</div>


 <div>
  <div>
   <input type="checkbox" id="Checkbox3" name="cCheckbox3" class="custom-control-input" (change)="checkSelected(checkBox[3].label)">
   <label class="label" for="Checkbox3" >first</label>
  </div>
  <div>
  <input type="checkbox" id="Checkbox4" name="cCheckbox4" class="custom-control-input" (change)="checkSelected(checkBox[4].label)">
   <label class="label" for="Checkbox4" >first</label>
  </div>
  <div>
  <input type="checkbox" id="Checkbox5" name="cCheckbox5" class="custom-control-input" (change)="checkSelected(checkBox[5].label)">
   <label class="label" for="Checkbox5" >first</label>
  </div>
</div>

Likewise I have two more separate divs in the same html file which contains checkboxes. What I need to do is onclick of first checkbox in first div ,I need to disabled every other checkboxes from the first div,second div & third.

As I'm totally new to angular I have no idea how to disable here. I have tried using ng-disabled but it seems not working. Can someone help me with this?

Answer 1

For Angular 2+, you can enable / disable the checkbox by setting the disabled attribute on the input type=checkbox

Use: [attr.disabled]="isDisabled ? true : null"

Note here that [attr.disabled]="isDisabled alone will not work. You will need to explicitly set disabled attribute to null for removing disabled attribute from the disabled checkbox.

<input type="checkbox" [attr.disabled]="isDisabled ? true : null" />