[Solved] In this code snippet:this.form = new FormGroup({ age: new FormControl(25)});this.form.controls.age.markAsPristine();console.log(this.form.controls.age.pristine);The console logs false. Why? | Angular

Angular - Reactive Forms

In this code snippet:

this.form = new FormGroup({
  age: new FormControl(25)
});
this.form.controls.age.markAsPristine();
console.log(this.form.controls.age.pristine);

The console logs false. Why?

AmarkAsPristine() was not called correctly

BThe control value was changed after initialization

CmarkAsPristine() sets pristine to true, so false is unexpected

DThe control was never dirty, so pristine is false

Step-by-Step Solution

Solution:

Step 1: Understand pristine and dirty relationship
Pristine means the control value has not changed since initialization; dirty means it has changed.
Step 2: Analyze why pristine is false after markAsPristine()
If the control value was changed after initialization, markAsPristine() resets the flag, but if value changed again later, pristine becomes false.
Final Answer:
The control value was changed after initialization -> Option B
Quick Check:
Value change after init makes pristine false [OK]

Quick Trick: Changing value after markAsPristine() resets pristine false [OK]

Common Mistakes:

MISTAKES

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In this code snippet: