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multipleOf

Validate that a numeric value is an exact multiple of a given divisor (value % n === 0).

Signature​

NguardValidators.Number.multipleOf(n: number): ValidatorFn
ParameterTypeDescription
nnumberThe divisor

Reactive forms​

import { FormControl } from '@angular/forms';
import { NguardValidators } from 'ng-nguard';

// Multiples of 5 — accepts 0, 5, 10, -5, etc.
const step = new FormControl('', [NguardValidators.Number.multipleOf(5)]);

// Multiples of 0.5 — accepts 0, 0.5, 1, 1.5, ...
const halves = new FormControl('', [NguardValidators.Number.multipleOf(0.5)]);

Template-driven forms​

<input ngModel name="step" [nguardMultipleOf]="5" />

Error key​

{ multipleOf: true }

Notes​

  • Zero is a multiple of any non-zero divisor (0 % n === 0).
  • Negative multiples pass — -10 is a multiple of 5.
  • Fractional divisors work for clean cases (0.5, 0.25). Floating-point arithmetic may produce surprises for irrational values; rely on this for human-friendly steps, not high-precision math.
  • Numeric strings work — '15' passes multipleOf(5).
  • null, undefined, empty string, NaN, Infinity all fail.

See also​

  • even — equivalent to multipleOf(2) for integers
  • integer — combine if you want "integer multiple of N"
  • decimal — different precision concept (decimal-place count, not divisibility)