The basic knowledge data type of the JavaScript program. {0912}

JS scripting language:

This is the name of Jaxascript.

JS is the scripting language used within the Web page

JS is a very powerful language.

The basic syntax of JS

Comment Syntax: single-line comment//Multiline comment/**/

Output syntax: Double-label Formula:<script> formula content </script>
Alert ("message") formula content} This code is a popup message on the page

Confirm ("Information"); Formula content} This code pops up a dialog box that interacts with the user. There is {OK} {cancel}
Prompt ("information") formula content} This code pops up a dialog box that lets the user enter

Embed JS code:
General JS Code is at the bottom, so try to write down.
Formula format <script type= "Text/javascript" ></script>

Basic knowledge of the program:

JS all the characters are all English half-width

In the case of a large department, a semicolon is added after each statement ends;

After each piece of code, add a newline {carriage return} so that the code you enter looks neat and tidy.

The program echoes back and forth. Preceded by a parenthesis "(" There must be a parenthesis end after ")"

Data type: Data stored in a program, stored in a name called a variable
Strongly typed languages: data storage needs to exist in the corresponding data type variables
Weakly typed languages: non-differentiated types when data is stored (type auto-conversion)

Strong language code type:
Shaping (integer) int

Single-precision fractional float

Decimal doble with double precision

Fractional decimal

Uncommon type, currency type money

Character Char

Strings string

boolean bool True True false-false

Date Time Type datetime

Variable definition:

var a = 10;

If you define a decimal or integer variable, the value after the equal sign is written directly

If you define a string variable, the value after the equals sign needs double or single quotation marks

Type conversion: parseint

The

JavaScript program basic knowledge data type. {0912}