Parameters « Functions « PHP

1.Functions and References
2.A function that takes a reference for an argument
3.Declaring a Function with Arguments
4.Function with default parameters
5.Passing Variables as a Reference to the Argument of a Function
6.Passing an Argument to a Function by Value
7.Using a Function Call to Pass an Argument to a Function by Reference
8.Declaring a Function That Requires Arguments
9.Function with an Optional Argument

10.A Function with an Optional Argument
11.Accessing Function Parameters
12.All optional arguments
13.Capturing a return value
14.Changing argument values
15.Defining and Calling a two-argument function,
16.Function Arguments
17.Function with two parameters
18.Creating Functions That Take a Variable Number of Arguments
19.Creating a capitalize function with a default parameter $each
20.Default Parameters
21.Define whether a variable is passed by value or reference
22.Passing By Reference
23.Making arguments be passed by reference
24.Using Optional Parameters