What is javascript syntax

JavaScript syntax is a set of rules that defines the language structure of JavaScript; JavaScript is a scripting language and a lightweight but powerful programming language.

The operating environment of this article: windows7 system, javascript version 1.8.5, Dell G3 computer.

What is the syntax of javascript?

JavaScript syntax is a set of rules that defines the language structure of JavaScript.

var x, y;// 如何声明变量
x = 7; y = 8;// 如何赋值
z = x + y;// 如何计算值

JavaScript Values

JavaScript statements define two types of values: mixed values ​​and variable values.

Mixed values ​​are called literals. Variable values ​​are called variables.

JavaScript literals

The most important rule for writing mixed values ​​is:

You can write values ​​with or without a decimal point:

15.90
10011

A string is text, surrounded by double or single quotes:

"Bill Gates"
'Bill Gates'

JavaScript Variables

In programming languages, variables are used to store data values.

JavaScript uses the var keyword to declare variables. The

= sign is used to assign a value to a variable.

In this example, x is defined as a variable. Then, the value assigned to x is 7:

var x;
x = 7;

For a more detailed introduction to JavaScript syntax, please visit the "javascript Syntax" chapter in the manual.

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