JavaScript functions self-invoking

1. A function is an event-driven or reusable block of code that executes when it is invoked.

2. Enclose the function in "()", followed by a "()"

3. JavaScript function's built-in object arguments object, which contains the parameter array of the function call!

4. Function call method, function is object, method of Object call (), apply () to invoke function!

Notice:

1. js Call function can not contain parameters, not to the parameter value can also Oh!    When you call a function, you can pass a value to it, which is called a parameter. is actually the arguments object is empty!

2. Function elevation (hoisting) promotes the current scope to the previous behavior. Elevation (hoisting) applies the declaration of a variable to a statement of the function.

3. A function is defined as an object's property, called an object method. The function is called the constructor of the object if it is used to create a new object.

JavaScript functions self-invoking