WXS入门教程-数据类型判断constructor和typeof

数据类型判断

constructor 属性

数据类型的判断可以使用 constructor 属性。

示例代码：

var number = 10;
console.log( "Number" === number.constructor );

var string = "str";
console.log( "String" === string.constructor );

var boolean = true;
console.log( "Boolean" === boolean.constructor );

var object = {};
console.log( "Object" === object.constructor );

var func = function(){};
console.log( "Function" === func.constructor );

var array = [];
console.log( "Array" === array.constructor );

var date = getDate();
console.log( "Date" === date.constructor );

var regexp = getRegExp();
console.log( "RegExp" === regexp.constructor );

typeof

使用 typeof 也可以区分部分数据类型。

示例代码：

var number = 10;
var boolean = true;
var object = {};
var func = function(){};
var array = [];
var date = getDate();
var regexp = getRegExp();

console.log( 'number' === typeof number );
console.log( 'boolean' === typeof boolean );
console.log( 'object' === typeof object );
console.log( 'function' === typeof func );
console.log( 'object' === typeof array );
console.log( 'object' === typeof date );
console.log( 'object' === typeof regexp );

console.log( 'undefined' === typeof undefined );
console.log( 'object' === typeof null );