The skeleton of JavaScript--Grammatical composition (i)

JavaScript, as a weakly typed language, has a large part of its grammatical rules that are based on the C language or other C-language style functions, but each language has its own grammatical features, which form the skeleton of the language.

All names are case-sensitive.

The following two rules are required for identifiers, such as names or functions that refer to variable function properties:

1. The first character must be a letter, an underscore (_), or a dollar sign ($);
2. Other characters can be letters, underscores, numbers, and dollar signs.

It is also important to note that JavaScript identifiers are best used in camel-like notation.

Third, comments. similar to the C language style, there are the following two types:

This is a single-line comment

/*

* This is a

* Multi-line

* Notes

/

Iv. statements. Although not strictly required, it is best to end the semicolon; code blocks with {} have better serviceability for code readability.

Keywords and reserved words. a keyword is a word that has a special purpose, and he cannot be used as an identifier, and a reserved word refers to a word that might be used as a keyword in the future. Here no more one by one repeat.

Six, variable. JavaScript variables can hold any type of data, which acts as a placeholder. For variables, it is important to note that VAR can manipulate a defined variable, but that the variable defined is a local variable, and a variable defined without VAR can be a global variable, but it is also not recommended.

The skeleton of JavaScript--Grammatical composition (i)