Validation Rules

isRequired()

Tests if there is a value.

import { isRequired } from '@formiz/validations'
<MyField
name="fieldName"
validations={[
{
rule: isRequired(),
message: 'This field is required',
},
]}
>

isNotEmptyString()

Tests if a string has not only spaces.

import { isNotEmptyString } from '@formiz/validations'
<MyField
name="fieldName"
validations={[
{
rule: isNotEmptyString(),
message: 'This field can\'t be empty',
},
]}
>

isNotEmptyArray()

Tests if an array is not empty.

import { isNotEmptyArray } from '@formiz/validations'
<MyField
name="fieldName"
validations={[
{
rule: isNotEmptyArray(),
message: 'This array can\'t be empty',
},
]}
>

isEmail()

Tests if a string is a valid email.

import { isEmail } from '@formiz/validations'
<MyField
name="fieldName"
validations={[
{
rule: isEmail(),
message: 'This is not a valid email',
},
]}
>

isNumber()

Tests if the value is a number.

import { isNumber } from '@formiz/validations'
<MyField
name="fieldName"
validations={[
{
rule: isNumber(),
message: 'This is not a number',
},
]}
>

isMinNumber(min)

Tests if the value is a number and above a min value.

import { isMinNumber } from '@formiz/validations'
<MyField
name="fieldName"
validations={[
{
rule: isMinNumber(10),
message: 'Should be a number over 10',
},
]}
>

isMaxNumber(max)

Tests if the value is a number and under a max value.

import { isMaxNumber } from '@formiz/validations'
<MyField
name="fieldName"
validations={[
{
rule: isMaxNumber(10),
message: 'Should be a number under 10',
},
]}
>

isInRangeNumber(min, max)

Tests if the value is a number and in a range between a min and a max.

import { isInRangeNumber } from '@formiz/validations'
<MyField
name="fieldName"
validations={[
{
rule: isInRangeNumber(1, 5),
message: 'Should be a number between 1 and 5',
},
]}
>

isPercentage()

Tests if the value is a number between 0 and 100.

import { isInRangeNumber } from '@formiz/validations'
<MyField
name="fieldName"
validations={[
{
rule: isPercentage(),
message: 'This is not a valid percentage',
},
]}
>

isLength(length)

Tests if a string or an array has a specific length.

import { isLength } from '@formiz/validations'
<MyField
name="fieldName"
validations={[
{
rule: isLength(4),
message: 'This has not a length of 4',
},
]}
>

isMinLength(min)

Tests if a string or an array has a minimum length.

import { isMinLength } from '@formiz/validations'
<MyField
name="fieldName"
validations={[
{
rule: isMinLength(4),
message: 'This should at least have a length of 4',
},
]}
>

isMaxLength(max)

Tests if a string or an array has a maximum length.

import { isMaxLength } from '@formiz/validations'
<MyField
name="fieldName"
validations={[
{
rule: isMaxLength(4),
message: 'This should have a length of 4 or less',
},
]}
>

isPattern(pattern)

Tests if a string matches a REGEX pattern.

import { isMaxLength } from '@formiz/validations'
<MyField
name="fieldName"
validations={[
{
rule: isPattern('hello'),
message: 'Must contain "hello"',
},
{
rule: isPattern('^[a-z]*$'),
message: 'Must only contain lowercase letters',
},
]}
>
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