Helpers

Following is the list of helpers used internally by VineJS to perform type-checking or sometimes narrow down the types. You might want to use them inside your custom rules or union conditionals.

isTrue

Returns true when the value is one of the following.

• true
• 1
• "1"
• "true"
• "on"

vine.helpers.isTrue(true) // true
vine.helpers.isTrue(1) // true
vine.helpers.isTrue("1") // true
vine.helpers.isTrue("true") // true
vine.helpers.isTrue("on") // true

isFalse

Returns true when the value is one of the following.

• false
• 0
• "0"
• "false"

vine.helpers.isFalse(false) // true
vine.helpers.isFalse(0) // true
vine.helpers.isFalse("0") // true
vine.helpers.isFalse("false") // true

isString

Check if the field value is a valid string. The method narrows down the type of value to string.

vine.helpers.isString(value) // value is 'string'

isObject

Check if the field value is a plain JavaScript object. The method filters out null and Arrays and does not consider them as Objects.

vine.helpers.isObject(value) // value is Record<string, unknown>

vine.helpers.isObject<number>(value) // value is Record<string, number>

isArray

Check if the field value is an Array.

vine.helpers.isArray(value) // value is unknown[]
vine.helpers.isArray<string>(value) // value is string[]

isNumeric

Check if the value is a number or a string representation of a number.

vine.helpers.isNumeric(32) // true
vine.helpers.isNumeric('32') // true
vine.helpers.isNumeric('121.09') // true
vine.helpers.isNumeric('49.00') // true

hasDecimals

Check if a number value has a fixed or a range of decimal places. The hasDecimals method accepts a number data type for the value input.

vine.helpers.hasDecimals(32.12, [0, 2]) // true
vine.helpers.hasDecimals(32, [0, 2]) // true
vine.helpers.hasDecimals(32, [2]) // false
vine.helpers.hasDecimals(32.101, [2]) // false

asNumber

Casts the value to a number using the Number method. Returns NaN when unable to cast.

vine.helpers.asNumber('32') // 32
vine.helpers.asNumber('32.12') // 32.12
vine.helpers.asNumber('32.00') // 32
vine.helpers.asNumber('foo') // NaN

asBoolean

Casts the value to a boolean.

• [true, 1, "1", "true", "on"] will be converted to true.
• [false, 0, "0", "false"] will be converted to false.
• Everything else will return null. So make sure to handle that case.

vine.helpers.asBoolean('true') // true
vine.helpers.asBoolean('on') // true
vine.helpers.asBoolean('false') // false
vine.helpers.asBoolean('foo') // null

const output = vine.helpers.asBoolean(value)
if (output !== null) {
}

Validator.js validators

Alongside the VineJS helpers, you may also use the vine.helpers object to access the following methods exported by the validator.js library.

• isEmail
• isURL
• isAlpha
• isAlphaNumeric
• isIP
• isUUID
• isAscii
• isCreditCard
• isIBAN
• isJWT
• isLatLong
• isMobilePhone
• isPassportNumber
• isPostalCode
• isSlug
• isDecimal
• mobileLocales
• passportCountryCodes
• postalCountryCodes
• isHexColor

vine.helpers.isEmail('foo@bar.com', {
  allow_ip_domain: false,
})

vine.helpers.isURL('https://foo.com', {
  require_protocol: true,
  allow_query_components: false,
})

vine.helpers.isPassportNumber('passport-number', {
  countryCode: 'IN'
})