Class: CheckUtil

CheckUtil

new CheckUtil()

util/CheckUtil.js, line 16

类型验证工具

Example

导入类型检查工具

// ES5引入方式
const { CheckUtil } = zondy.util

// ES6引入方式
import { CheckUtil } from '@mapgis/webclient-common'
const ok = CheckUtil.isBoolean(true)

Methods

CheckUtil.isArguments(value){boolean}

util/CheckUtil.js, line 477

Checks if value is likely an arguments object.

Name Type Description
value *

The value to check.
Since:
  • 0.1.0
Returns:
Type Description
boolean Returns true if value is an arguments object, else false.
Example
isArguments(function() { return arguments }())
// => true

isArguments([1, 2, 3])
// => false

CheckUtil.isArray(value){boolean}

util/CheckUtil.js, line 266

Checks if value is Array.

Name Type Description
value *

The value to check.
Since:
  • 0.1.0
Returns:
Type Description
boolean Returns true if value is Array, else false.
Example
isArray([1,2,3])
// => true

CheckUtil.isArrayLike(value){boolean}

util/CheckUtil.js, line 293

Checks if value is array-like. A value is considered array-like if it's not a function and has a value.length that's an integer greater than or equal to 0 and less than or equal to Number.MAX_SAFE_INTEGER.

Name Type Description
value *

The value to check.
Since:
  • 4.0.0
Returns:
Type Description
boolean Returns true if value is array-like, else false.
Example
isArrayLike([1, 2, 3])
// => true

isArrayLike(document.body.children)
// => true

isArrayLike('abc')
// => true

isArrayLike(Function)
// => false

CheckUtil.isArrayLikeObject(value){boolean}

util/CheckUtil.js, line 320

This method is like isArrayLike except that it also checks if value is an object.

Name Type Description
value *

The value to check.
Since:
  • 4.0.0
Returns:
Type Description
boolean Returns true if value is an array-like object, else false.
Example
isArrayLikeObject([1, 2, 3])
// => true

isArrayLikeObject(document.body.children)
// => true

isArrayLikeObject('abc')
// => false

isArrayLikeObject(Function)
// => false

CheckUtil.isBase64(value){boolean}

util/CheckUtil.js, line 506

Check if value is a base64

Name Type Description
value *
Returns:
Type Description
boolean Returns true if value is a base64

CheckUtil.isBoolean(value){boolean}

util/CheckUtil.js, line 55

Checks if value is classified as a boolean primitive or object.

Name Type Description
value *

The value to check.
Returns:
Type Description
boolean Returns true if value is a boolean, else false.
Example
isBoolean(false)
// => true

isBoolean(null)
// => false

CheckUtil.isElement(value){boolean}

util/CheckUtil.js, line 430

Checks if value is likely a DOM element.

Name Type Description
value *

The value to check.
Since:
  • 0.1.0
Returns:
Type Description
boolean Returns true if value is a DOM element, else false.
Example
isElement(document.body)
// => true

isElement('')
// => false

CheckUtil.isError(value){boolean}

util/CheckUtil.js, line 450

Checks if value is an Error, EvalError, RangeError, ReferenceError, SyntaxError, TypeError, or URIError object.

Name Type Description
value *

The value to check.
Since:
  • 3.0.0
Returns:
Type Description
boolean Returns true if value is an error object, else false.
Example
isError(new Error)
// => true

isError(Error)
// => false

CheckUtil.isFunction(value){boolean}

util/CheckUtil.js, line 141

Checks if value is classified as a Function object.

Name Type Description
value *

The value to check.
Since:
  • 0.1.0
Returns:
Type Description
boolean Returns true if value is a function, else false.
Example
isFunction(class Any{})
// => true

isFunction(() => {})
// => true

isFunction(async () => {})
// => true

isFunction(function * Any() {})
// => true

isFunction(Math.round)
// => true

isFunction(/abc/)
// => false

CheckUtil.isLength(value){boolean}

util/CheckUtil.js, line 169

Checks if value is a valid array-like length.

Note: This method is loosely based on ToLength.

Name Type Description
value *

The value to check.
Since:
  • 4.0.0
Returns:
Type Description
boolean Returns true if value is a valid length, else false.
Example
isLength(3)
// => true

isLength(Number.MIN_VALUE)
// => false

isLength(Infinity)
// => false

isLength('3')
// => false

CheckUtil.isNative(value){boolean}

util/CheckUtil.js, line 497

Checks if value is a pristine native function.

Name Type Description
value *

The value to check.
Since:
  • 3.0.0
Returns:
Type Description
boolean Returns true if value is a native function, else false.
Example
isNative(Array.prototype.push)
// => true

isNative(isDate)
// => false

CheckUtil.isNil(value){boolean}

util/CheckUtil.js, line 342

Checks if value is null or undefined.

Name Type Description
value *

The value to check.
Since:
  • 4.0.0
Returns:
Type Description
boolean Returns true if value is nullish, else false.
Example
isNil(null)
// => true

isNil(void 0)
// => true

isNil(NaN)
// => false

CheckUtil.isNull(value){boolean}

util/CheckUtil.js, line 250

Checks if value is null.

Name Type Description
value *

The value to check.
Since:
  • 0.1.0
Returns:
Type Description
boolean Returns true if value is null, else false.
Example
isNull(null)
// => true

isNull(void 0)
// => false

CheckUtil.isNumber(value){boolean}

util/CheckUtil.js, line 371

Checks if value is classified as a Number primitive or object.

Note: To exclude Infinity, -Infinity, and NaN, which are classified as numbers, use the Number.isFinite method.

Name Type Description
value *

The value to check.
Since:
  • 0.1.0
See:
  • isInteger, toInteger, toNumber
Returns:
Type Description
boolean Returns true if value is a number, else false.
Example
isNumber(3)
// => true

isNumber(Number.MIN_VALUE)
// => true

isNumber(Infinity)
// => true

isNumber('3')
// => false

CheckUtil.isObject(value){boolean}

util/CheckUtil.js, line 86

Checks if value is the language type of Object. (e.g. arrays, functions, objects, regexes, new Number(0), and new String(''))

Name Type Description
value *

The value to check.
Since:
  • 0.1.0
Returns:
Type Description
boolean Returns true if value is an object, else false.
Example
isObject({})
// => true

isObject([1, 2, 3])
// => true

isObject(Function)
// => true

isObject(null)
// => false

CheckUtil.isObjectLike(value){boolean}

util/CheckUtil.js, line 110

Checks if value is object-like. A value is object-like if it's not null and has a typeof result of "object".

Name Type Description
value *

The value to check.
Returns:
Type Description
boolean Returns true if value is object-like, else false.
Example
isObjectLike({})
// => true

isObjectLike([1, 2, 3])
// => true

isObjectLike(Function)
// => false

isObjectLike(null)
// => false

CheckUtil.isPlainObject(value){boolean}

util/CheckUtil.js, line 401

Checks if value is a plain object, that is, an object created by the Object constructor or one with a [[Prototype]] of null.

Name Type Description
value *

The value to check.
Since:
  • 0.8.0
Returns:
Type Description
boolean Returns true if value is a plain object, else false.
Example
function Foo() {
  this.a = 1
}

isPlainObject(new Foo)
// => false

isPlainObject([1, 2, 3])
// => false

isPlainObject({ 'x': 0, 'y': 0 })
// => true

isPlainObject(Object.create(null))
// => true

CheckUtil.isString(value){boolean}

util/CheckUtil.js, line 188

Checks if value is classified as a String primitive or object.

Name Type Description
value *

The value to check.
Since:
  • 0.1.0
Returns:
Type Description
boolean Returns true if value is a string, else false.
Example
isString('abc')
// => true

isString(1)
// => false

CheckUtil.isSymbol(value){boolean}

util/CheckUtil.js, line 211

Checks if value is classified as a Symbol primitive or object.

Name Type Description
value *

The value to check.
Since:
  • 4.0.0
Returns:
Type Description
boolean Returns true if value is a symbol, else false.
Example
isSymbol(Symbol.iterator)
// => true

isSymbol('abc')
// => false

CheckUtil.isUndefined(value){boolean}

util/CheckUtil.js, line 231

Checks if value is undefined.

Name Type Description
value *

The value to check.
Since:
  • 0.1.0
Returns:
Type Description
boolean Returns true if value is undefined, else false.
Example
isUndefined(void 0)
// => true

isUndefined(null)
// => false