[Solved] Identify the error in this custom validator code snippet: function minLengthFive(control: AbstractControl) { if (control.value.length | Angular

Angular - Reactive Forms

Identify the error in this custom validator code snippet:

function minLengthFive(control: AbstractControl) {
  if (control.value.length < 5) {
    return { minLengthFive: true };
  }
}

AIncorrect error object key name

BMissing return null for valid input

CUsing control.value.length without checking null

DValidator should return boolean instead of object

Step-by-Step Solution

Solution:

Step 1: Check for runtime errors
The code accesses control.value.length without checking if control.value is null or undefined, causing TypeError when value is null (common for new FormControls).
Step 2: Angular validator best practice
Always check if (control.value == null) return null; before accessing properties like length. Explicit return null; for valid cases is also recommended.
Final Answer:
Using control.value.length without checking null -> Option C
Quick Check:
control.value can be null causing crash [OK]

Quick Trick: Always check control.value != null before .length [OK]

Common Mistakes:

MISTAKES

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