var a = 10;var PI = 3.141592653589793;
toString;toLocaleString;valueOf;toFixed;toExponential;toPrecision。For information on using the above methods, refer to the ES5 standard.
'hello world';"hello world";
constructor:Returns the string "String";length。For explanations of properties other than constructor, refer to the ES5 standard.
toString;valueOf;charAt;charCodeAt;concat;indexOf;lastIndexOf;localeCompare;match;replace;search;slice;split;substring;toLowerCase;toLocaleLowerCase;toUpperCase;toLocaleUpperCase;trim。For information on using the above methods, refer to the ES5 standard.
constructor:Returns the string "Boolean".toString;valueOf。For information on using the above methods, refer to the ES5 standard.
var o = {} // Generates a new empty object.// Generates a new non-empty object.o = {'string' : 1, //The object’s key can be a string.const_var : 2, //The object’s key can also be an identifier that conforms to the variable definition rules.func : {}, //The object’s value can be of any type.};//Object property read operationconsole.log(1 === o['string']);console.log(2 === o.const_var);//Object property write operationo['string']++;o['string'] += 10;o.const_var++;o.const_var += 10;//Object property read operationconsole.log(12 === o['string']);console.log(13 === o.const_var);
console.log("Object" === {k:"1",v:"2"}.constructor)
//Method 1function a (x) {return x;}//Method 2var b = function (x) {return x;}
var a = function (x) {return function () { return x;}}var b = a(100);console.log( 100 === b() );
var a = function(){console.log(3 === arguments.length);console.log(100 === arguments[0]);console.log(200 === arguments[1]);console.log(300 === arguments[2]);};a(100,200,300);
var func = function (a,b,c) { }console.log("Function" === func.constructor);console.log(3 === func.length);console.log("[function Function]" === func.toString());
var a = []; // Generates a new empty array.a = [1,"2",{},function(){}]; // Generates a new non-empty array, with array elements of any type.
constructor: Returns the string "Array";length。For explanations of properties other than constructor, refer to the ES5 standard.
toString;concat;join;pop;push;reverse;shift;slice;sort;splice;unshift;indexOf;lastIndexOf;every;some;forEach;map;filter;reduce;reduceRight。For information on using the above methods, refer to the ES5 standard.
getDate()getDate(milliseconds)getDate(datestring)getDate(year, month[, date[, hours[, minutes[, seconds[, milliseconds]]]]])
var date = getDate(); //Returns the current time object.date = getDate(1500000000000);// Fri Jul 14 2017 10:40:00 GMT+0800 (China Standard Time)date = getDate('2017-7-14');// Fri Jul 14 2017 00:00:00 GMT+0800 (China Standard Time)date = getDate(2017, 6, 14, 10, 40, 0, 0);// Fri Jul 14 2017 10:40:00 GMT+0800 (China Standard Time)
toString;toDateString;toTimeString;toLocaleString;toLocaleDateString;toLocaleTimeString;valueOf;getTime;getFullYear;getUTCFullYear;getMonth;getUTCMonth;getDate;getUTCDate;getDay;getUTCDay;getHours;getUTCHours;getMinutes;getUTCMinutes;getSeconds;getUTCSeconds;getMilliseconds;getUTCMilliseconds;getTimezoneOffset;setTime;setMilliseconds;setUTCMilliseconds;setSeconds;setUTCSeconds;setMinutes;setUTCMinutes;setHours;setUTCHours;setDate;setUTCDate;setMonth;setUTCMonth;setFullYear;setUTCFullYear;toUTCString;toISOString;toJSON。For information on using the above methods, refer to the ES5 standard.
getRegExp(pattern[, flags])
var a = getRegExp("x", "img");console.log("x" === a.source);console.log(true === a.global);console.log(true === a.ignoreCase);console.log(true === a.multiline);
constructor:Returns the string "RegExp";source;global;ignoreCase;multiline;lastIndex。For explanations of properties other than constructor, refer to the ES5 standard.
exec;test;toString。For information on using the above methods, refer to the ES5 standard.
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 );
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 );
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