One. Comment syntax
1. Single-line comment//
2. Multi-line Comment/**/
Two. Syntax output
1.alert (Info): Popup information
2.confirm (info): Pop Up a dialog box with user interaction
3.prompt (info): POPs up a dialog box for the user to enter
Three. Embed code
1. Write down as much as possible
2.<script style= "Textjavasprit" ></script>
Four. Basic knowledge of the program
1. All characters are in English half-width
2. In most cases, a semicolon is added after the end of each statement
3. Line breaks after each piece of code ends
4. Pre-and post-process echoes (preceded by a parenthesis "(must have a parenthesis end)")
Five. Data type
1. The data is stored in the program, and the stored name is called a variable
2. Data storage needs to exist in the corresponding data type variables: strongly typed language
3. The data is stored in a non-differentiated type (type auto-conversion): Weakly typed language
5. Type: (integer) int, (single-precision decimal float), (decimal number Double), (decimal: decimal), (currency type money), (character char), (string literal), (Boolean bool:true true). False), (date Time type datetime)
6. Variable definition: var:a=10; (if a variable with a decimal or an integer is defined, the value after the equal sign is written directly) (if you define a string variable, the value after the equals sign needs to be double or single quotation marks)
7. Type conversion: parseint
8. Operator Expressions:
JS scripting language (full name Java script: scripting language used in Web pages: very powerful language): basic syntax