return nan

Check the relevant information to know:function Stringtodate (DATESTR) {if (typeof datestr = = "undefined") return new Date ();if (typeof datestr = = "Date") return datestr;var converted = Date.parse (DATESTR);var mydate = new Date (converted);if

Operators include: arithmetic operators, bitwise operators, relational operators, and equality operators.Unary operator1, can only operate a worthy operator, that is, increment and decrement operators;2, Increment (+ +) and decrement (-) operators

Javascript data type conversion methods include conversion functions, forced type conversion, and weak type conversion using JS variables. 1. conversion functions: JS provides two conversion functions: parseint () and parsefloat. The former

Http://www.cnblogs.com/Ninputer/archive/2011/08/18/2145045.html   A number of days ago, the technical master vczh developed a function image rendering program that can draw an image with the equation f (x, y) = 0. The principle is to bring the

1. Math Object1.1 Introduction The Math object, which is a mathematical object, provides a mathematical calculation of the data, such as acquiring absolute value, rounding up, and so on. No constructors, cannot be initialized, provides only static

1. Math Object 1.1 Introduction The Math object, which is a mathematical object, provides a mathematical calculation of the data, such as acquiring absolute value, rounding up, and so on. No constructors, cannot be initialized, provides only

Here's a detailed talk about the difference between Boolean, Nnumber, and String coercion of type conversions in Javascript. We know that Boolean (value) converts a value to a Boolean type, and Nnumber (value) converts a value to a number (integer

Type conversions can be divided into implicit conversions and explicit conversions, which are called implicit conversions, which are automatically converted by programs at run time, and explicit conversions are artificially cast on types. JavaScript

Javascript type conversion. Directory: 1: pseudo object 2: convert to a string 3: Numeric to string 4: convert to a number 5: Convert to Boolean 6: difference between Number () and parseInt () 7: differences between String () and toString () 1:

First, the Transformation function Boolean ()The values of all types in ECMAScript have values that are equivalent to the Boolean value (True and false). To convert a value to its corresponding Boolean value, you can call the Transform function

This article mainly introduces the basic types and reference types of JavaScript. The basic types also include type conversion. If you are interested, refer I. Value Type We mentioned the basic and reference types as early as we introduced the JS

DescriptionIntroducing JavaScript data typesDirectory Objective Reference sources Front-facing technical requirements 6 Types of data for JavaScript What 6 types of data Undefined type Null

One. JavaScript Array classCreate a JS array in two different ways:var arr = []; Orvar arr = new Array ();() can specify the length, or can not be specified, refers to the non-specified is irrelevant, because the length of the array in JS is

Chapter III Basic Concepts Everything in ECMAScript (variables, function names, and operators) is case-sensitive. Identifiers are the names of variables, functions, attributes, or parameters of a function. The constituent rules for

Original: Learn JavaScript from the beginning (v)--operator (ii)One, multiplicative sex operator1. Multiplication: *Some special rules for multiplication operators: If the operand is a numeric value, it is calculated by normal

One, multiplicative sex operator1. Multiplication: *Some special rules for multiplication operators: If the operand is a numeric value, it is calculated by normal multiplication, and if the product exceeds the representation range of the

Main.swift//Operator and expression (i)////Created by Goddog on 15/6/23. Copyright (c) 2015 Goddog. All rights reserved. Import Foundation//mark:-Assignment operator//with = as assignment operator var str = "Swift" var pi:double = 3.14 var

Introduction: A New day, insist on learning, summary. Yesterday's article looked again today, found that the updated knowledge point is really a little less, today to write more than a line. Then this blog post continues to summarize the knowledge

Article Starter: http://www.cnblogs.com/sprying/p/4349426.htmlThis article lists the general JS type detection method, is the construction of JS knowledge system of a small piece, this article is my early summary.In JS, there are 5 basic data types

I. GrammarEverything in 1.javascirpt (variables, function names, and operators) is strictly case-sensitive.2.javascript (identifier)An identifier is a variable, a function, the name of a property, or an argument to a function.Naming rules: The first