What is the function construct used for

Question

I have been noticing   construct a lot with classes  I did a little reading and surfing the web  but I couldn t find an explanation I could understand  I am just beginning with OOP   I was wondering if someone could give me a general idea of what it is  and then a simple example of how it is used with PHP

User · Answer

Its another way to declare the constructor. You can also use the class name, for ex:

class Cat
{
    function Cat()
    {
        echo 'meow';
    }
}

and

class Cat
{
    function __construct()
    {
        echo 'meow';
    }
}

Are equivalent. They are called whenever a new instance of the class is created, in this case, they will be called with this line:

$cat = new Cat();

User · Answer

construct   is the method name for the constructor  The constructor is called on an object after it has been created  and is a good place to put initialisation code  etc   class Person        public function   construct                Code called for each new Person we create            person   new Person      A constructor can accept parameters in the normal manner  which are passed when the object is created  e g   class Person        public  name            public function   construct   name              this- gt name    name             person   new Person   Joe     echo  person- gt name    Unlike some other languages  e g  Java   PHP doesn t support overloading the constructor  that is  having multiple constructors which accept different parameters   You can achieve this effect using static methods   Note  I retrieved this from the log of the  at time of this writing  accepted answer

User · Answer

Its another way to declare the constructor. You can also use the class name, for ex:

class Cat
{
    function Cat()
    {
        echo 'meow';
    }
}

and

class Cat
{
    function __construct()
    {
        echo 'meow';
    }
}

Are equivalent. They are called whenever a new instance of the class is created, in this case, they will be called with this line:

$cat = new Cat();

User · Answer

A constructor allows you to initialize an object s properties upon creation of the object  If you create a   construct   function  PHP will automatically call this function when you create an object from a class  https   www w3schools com php php oop constructor asp

User · Answer

construct   is the method name for the constructor  The constructor is called on an object after it has been created  and is a good place to put initialisation code  etc   class Person        public function   construct                Code called for each new Person we create            person   new Person      A constructor can accept parameters in the normal manner  which are passed when the object is created  e g   class Person        public  name            public function   construct   name              this- gt name    name             person   new Person   Joe     echo  person- gt name    Unlike some other languages  e g  Java   PHP doesn t support overloading the constructor  that is  having multiple constructors which accept different parameters   You can achieve this effect using static methods   Note  I retrieved this from the log of the  at time of this writing  accepted answer

User · Answer

A constructor allows you to initialize an object s properties upon creation of the object  If you create a   construct   function  PHP will automatically call this function when you create an object from a class  https   www w3schools com php php oop constructor asp

User · Answer

I believe that function   construct          is a piece of code that can be reused again and again in substitution for TheActualFunctionName           If you change the CLASS Name you do not have to change within the code because the generic   construct refers always to the actual class name   whatever it is  You code less   or

User · Answer

The   construct method is used to pass in parameters when you first create an object--this is called  defining a constructor method   and is a common thing to do    However  constructors are optional--so if you don t want to pass any parameters at object construction time  you don t need it   So      Create a new class  and include a   construct method class Task        public  title      public  description       public function   construct  title   description            this- gt title    title           this- gt description    description              Create a new object  passing in a  title and  description  task   new Task  Learn OOP   This is a description        Try it and see var dump  task- gt title   task- gt description     For more details on what a constructor is  see the manual

User · Answer

construct is a method for initializing of new object before it is used  http   php net manual en language oop5 decon php object construct

User · Answer

construct was introduced in PHP5 and it is the right way to define your  well  constructors  in PHP4 you used the name of the class for a constructor   You are not required to define a constructor in your class  but if you wish to pass any parameters on object construction then you need one   An example could go like this   class Database     protected  userName    protected  password    protected  dbName     public function   construct    UserName   Password   DbName          this- gt userName    UserName       this- gt password    Password       this- gt dbName    DbName            and you would use this as   db   new Database    user name    password    database name       Everything else is explained in the PHP manual  click here

User · Answer

construct   is the method name for the constructor  The constructor is called on an object after it has been created  and is a good place to put initialisation code  etc   class Person        public function   construct                Code called for each new Person we create            person   new Person      A constructor can accept parameters in the normal manner  which are passed when the object is created  e g   class Person        public  name            public function   construct   name              this- gt name    name             person   new Person   Joe     echo  person- gt name    Unlike some other languages  e g  Java   PHP doesn t support overloading the constructor  that is  having multiple constructors which accept different parameters   You can achieve this effect using static methods   Note  I retrieved this from the log of the  at time of this writing  accepted answer

User · Answer

The   construct method is used to pass in parameters when you first create an object--this is called  defining a constructor method   and is a common thing to do    However  constructors are optional--so if you don t want to pass any parameters at object construction time  you don t need it   So      Create a new class  and include a   construct method class Task        public  title      public  description       public function   construct  title   description            this- gt title    title           this- gt description    description              Create a new object  passing in a  title and  description  task   new Task  Learn OOP   This is a description        Try it and see var dump  task- gt title   task- gt description     For more details on what a constructor is  see the manual

User · Answer

construct is a method for initializing of new object before it is used  http   php net manual en language oop5 decon php object construct

User · Answer

The constructor is a method which is automatically called on class instantiation  Which means the contents of a constructor are processed without separate method calls  The contents of a the class keyword parenthesis are passed to the constructor method

User · Answer

I believe that function   construct          is a piece of code that can be reused again and again in substitution for TheActualFunctionName           If you change the CLASS Name you do not have to change within the code because the generic   construct refers always to the actual class name   whatever it is  You code less   or

User · Answer

construct was introduced in PHP5 and it is the right way to define your  well  constructors  in PHP4 you used the name of the class for a constructor   You are not required to define a constructor in your class  but if you wish to pass any parameters on object construction then you need one   An example could go like this   class Database     protected  userName    protected  password    protected  dbName     public function   construct    UserName   Password   DbName          this- gt userName    UserName       this- gt password    Password       this- gt dbName    DbName            and you would use this as   db   new Database    user name    password    database name       Everything else is explained in the PHP manual  click here

User · Answer

construct is always called when creating new objects or they are invoked when initialization takes place it is suitable for any initialization that the object may need before it is used    construct method is the first method executed in class       class Test             function   construct  value1  value2                   echo  Inside Construct            echo  this- gt value1           echo  this- gt value2                       testObject     new Test  abc   123

User · Answer

Note  Parent constructors are not called implicitly if the child class defines a constructor  In order to run a parent constructor  a call to parent    construct   within the child constructor is required  If the child does not define a constructor then it may be inherited from the parent class just like a normal class method  if it was not declared as private

User · Answer

construct is always called when creating new objects or they are invoked when initialization takes place it is suitable for any initialization that the object may need before it is used    construct method is the first method executed in class       class Test             function   construct  value1  value2                   echo  Inside Construct            echo  this- gt value1           echo  this- gt value2                       testObject     new Test  abc   123

User · Answer

I think this is important to the understanding of the purpose of the constructor  Even after reading the responses here it took me a few minutes to realise and here is the reason  I have gotten into a habit of explicitly coding everything that is initiated or occurs  In other words this would be my cat class and how I would call it   class cat php  class cat       function speak             return  meow               somepage php  include  class cat php    mycat   new cat   speak   cat- gt speak    echo  speak    Where in  Logan Serman s given  class cat  examples it is assumed that every time you create a new object of class  cat  you want the cat to  meow  rather than waiting for you to call the function to make it meow   In this way my mind was thinking explicitly where the constructor method uses implicity and this made it hard to understand at first

User · Answer

I think this is important to the understanding of the purpose of the constructor  Even after reading the responses here it took me a few minutes to realise and here is the reason  I have gotten into a habit of explicitly coding everything that is initiated or occurs  In other words this would be my cat class and how I would call it   class cat php  class cat       function speak             return  meow               somepage php  include  class cat php    mycat   new cat   speak   cat- gt speak    echo  speak    Where in  Logan Serman s given  class cat  examples it is assumed that every time you create a new object of class  cat  you want the cat to  meow  rather than waiting for you to call the function to make it meow   In this way my mind was thinking explicitly where the constructor method uses implicity and this made it hard to understand at first

User · Answer

Note  Parent constructors are not called implicitly if the child class defines a constructor  In order to run a parent constructor  a call to parent    construct   within the child constructor is required  If the child does not define a constructor then it may be inherited from the parent class just like a normal class method  if it was not declared as private

User · Answer

construct simply initiates a class  Suppose you have the following code   Class Person      function   construct        echo  Hello            person   new Person       the result  Hello  will be shown    We did not create another function to echo the word  Hello   It simply shows that the keyword   construct is quite useful in initiating a class or an object

User · Answer

construct was introduced in PHP5 and it is the right way to define your  well  constructors  in PHP4 you used the name of the class for a constructor   You are not required to define a constructor in your class  but if you wish to pass any parameters on object construction then you need one   An example could go like this   class Database     protected  userName    protected  password    protected  dbName     public function   construct    UserName   Password   DbName          this- gt userName    UserName       this- gt password    Password       this- gt dbName    DbName            and you would use this as   db   new Database    user name    password    database name       Everything else is explained in the PHP manual  click here

User · Answer

I Hope this Help    lt  php        The code below creates the class     class Person              Creating some properties  variables tied to an object          public  isAlive   true          public  firstname          public  lastname          public  age              Assigning the values         public function   construct  firstname   lastname   age               this- gt firstname    firstname             this- gt lastname    lastname             this- gt age    age                        Creating a method  function tied to an object          public function greet               return  Hello  my name is      this- gt firstname          this- gt lastname      Nice to meet you   -                              Creating a new person called  boring 12345   who is 12345 years old  -       me   new Person  boring    12345   12345           Printing out  what the greet method returns     echo  me- gt greet           gt    For More Information You need to Go to codecademy com

User · Answer

construct simply initiates a class  Suppose you have the following code   Class Person      function   construct        echo  Hello            person   new Person       the result  Hello  will be shown    We did not create another function to echo the word  Hello   It simply shows that the keyword   construct is quite useful in initiating a class or an object

User · Answer

construct   is the method name for the constructor  The constructor is called on an object after it has been created  and is a good place to put initialisation code  etc   class Person        public function   construct                Code called for each new Person we create            person   new Person      A constructor can accept parameters in the normal manner  which are passed when the object is created  e g   class Person        public  name            public function   construct   name              this- gt name    name             person   new Person   Joe     echo  person- gt name    Unlike some other languages  e g  Java   PHP doesn t support overloading the constructor  that is  having multiple constructors which accept different parameters   You can achieve this effect using static methods   Note  I retrieved this from the log of the  at time of this writing  accepted answer

User · Answer

I Hope this Help    lt  php        The code below creates the class     class Person              Creating some properties  variables tied to an object          public  isAlive   true          public  firstname          public  lastname          public  age              Assigning the values         public function   construct  firstname   lastname   age               this- gt firstname    firstname             this- gt lastname    lastname             this- gt age    age                        Creating a method  function tied to an object          public function greet               return  Hello  my name is      this- gt firstname          this- gt lastname      Nice to meet you   -                              Creating a new person called  boring 12345   who is 12345 years old  -       me   new Person  boring    12345   12345           Printing out  what the greet method returns     echo  me- gt greet           gt    For More Information You need to Go to codecademy com

User · Answer

class Person   private  fname   private  lname    public function   construct  fname  lname      this- gt fname    fname     this- gt lname    lname        objPerson1   new Person  john   smith

User · Answer

The constructor is a method which is automatically called on class instantiation  Which means the contents of a constructor are processed without separate method calls  The contents of a the class keyword parenthesis are passed to the constructor method

User · Answer

Its another way to declare the constructor. You can also use the class name, for ex:

class Cat
{
    function Cat()
    {
        echo 'meow';
    }
}

and

class Cat
{
    function __construct()
    {
        echo 'meow';
    }
}

Are equivalent. They are called whenever a new instance of the class is created, in this case, they will be called with this line:

$cat = new Cat();

User · Answer

class Person   private  fname   private  lname    public function   construct  fname  lname      this- gt fname    fname     this- gt lname    lname        objPerson1   new Person  john   smith

User · Answer

Its another way to declare the constructor. You can also use the class name, for ex:

class Cat
{
    function Cat()
    {
        echo 'meow';
    }
}

and

class Cat
{
    function __construct()
    {
        echo 'meow';
    }
}

Are equivalent. They are called whenever a new instance of the class is created, in this case, they will be called with this line:

$cat = new Cat();

User · Answer

construct was introduced in PHP5 and it is the right way to define your  well  constructors  in PHP4 you used the name of the class for a constructor   You are not required to define a constructor in your class  but if you wish to pass any parameters on object construction then you need one   An example could go like this   class Database     protected  userName    protected  password    protected  dbName     public function   construct    UserName   Password   DbName          this- gt userName    UserName       this- gt password    Password       this- gt dbName    DbName            and you would use this as   db   new Database    user name    password    database name       Everything else is explained in the PHP manual  click here

[php] What is the function __construct used for?

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