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Adding Methods

2:18 with Alena Holligan

A function inside a class is called a method. These methods tell an object how to perform certain actions. We can access class methods to perform actions on data of the individual objects.

Methods

Functions within a class are called methods.

Referencing Objects

OOP allows objects to reference themselves using the keyword variable $this. When working within the scope of a method, use the keyword $this in the same way you would use the object name outside the class. The $this keyword indicates that we want to use the object’s own properties or methods, and allows us to have access to them within the class scope.

return $this->title . " by " . $this->source;

Note: Just like accessing the property outside the class, only the keyword $this starts with the dollar sign, we don’t use the dollar sign again for the properties and methods. Together $this, with the property name, make up a single variable.

  • 0:00

    Methods are class specific functions.

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    As such, the individual actions that an object will perform

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    are defined within these class methods.

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    When declaring a method, we also define the visibility.

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    Just like we did on properties.

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    The naming convention for methods is also the same as property.

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    Camel case.

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    Remember, that means the first word starts with a lowercase letter, and

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    all other words start with a capital letter.

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    Let's go back to work spaces, and add our first method.

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    Start by adding our visibility keyword, public, followed by function.

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    See, it really is a function.

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    Then our method name, displayRecipe.

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    Just like any other function, we use the opening and closing parentheses.

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    Then just like with our class, we want our curly braces to start on the next line.

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    Within our method we describe the action we want to perform.

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    For our methods to really be useful, we need them to have access to the other

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    methods and properties of their respective objects.

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    PHP allows objects to reference themselves using the keyword variable $this.

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    When working within the scope of a method use $this

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    in the same way that you would use the object name, outside the class.

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    The $this keyword indicates that we want to use the object's own properties or

  • 1:34

    methods, and allows us to have access to them within the class scope.

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    Let's start by returning the title and the source properties of the current object.

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    Just like accessing the property outside the class,

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    only the keyword $this starts with a dollar sign.

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    We don't use it again for the properties and methods.

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    Together $this, with the property name, make up a single variable.

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    Next, we'll cover how individual objects can access these methods.

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