Whether javascript variable naming is case-sensitive

This article mainly introduces whether the javascript variable naming is case-sensitive, has a certain reference value, interested friends can refer to, I hope you can learn a lot after reading this article, the following let the editor take you to understand it.

Javascript variable naming is case-sensitive, and all JavaScript variables must be identified by unique names called identifiers; identifiers can be short names or more descriptive names.

This article operating environment: windows7 system, javascript1.8.5 version, Dell G3 computer.

Javascript variable naming is case-sensitive.

The JavaScript variable is a container for storing data values.

JavaScript identifier

All JavaScript variables must be identified by a unique name.

These unique names are called identifiers.

Identifiers can be short names (such as x and y) or more descriptive names (age, sum, totalVolume).

The general rules for constructing variable names (unique identifiers) are:

Names can contain letters, numbers, underscores, and dollar signs

The name must begin with a letter

The name can also start with $and _ (but we won't do that in this tutorial)

Names are case-sensitive (y and Y are different variables)

Reserved words (such as keywords for JavaScript) cannot be used as variable names

Tip: JavaScript identifiers are case sensitive.

Assignment operator

In JavaScript, the equal sign (=) is the assignment operator, not the "equal" operator.

Note: the equals operator in JavaScript is = =.

Declare (create) JavaScript variables

Creating a variable in JavaScript is called a "declaration" variable.

You can declare the JavaScript variable through the var keyword:

Var carName

After declaration, the variable has no value. (technically, its value is undefined. )

To assign a value to a variable, use the equal sign:

CarName = "porsche"

You can assign values to a variable when you declare it:

Var carName = "porsche"

In the above example, we created a variable named carName and assigned the value "porsche" to it.

Then, we "output" this value in the HTML paragraph of id= "demo":

Example

Var carName = "porsche"; document.getElementById ("demo") [xss_clean] = carName; Thank you for reading this article carefully. I hope the article "whether the naming of javascript variables is case-sensitive" shared by the editor will be helpful to you. At the same time, I also hope that you will support us and pay attention to the industry information channel. More related knowledge is waiting for you to learn!