Using a addEventListener to call a forEach function

So I cant find any sources online that shows an eventListener triggering a function by click that is forEach based I know i'm doing something wrong here so can any one point me to the right direction.

This is my code

document.addEventListener('DOMContentLoaded',function(){



var numbers = [4, 9, 16, 25];



document.querySelector('button').addEventListener('click',numbers.forEach(myFunction))



function myFunction(item, index) {



  //create a new h1 element 

  var newH1 = document.createElement('h1'); 

  //

  

  //Insert content in the h1

  var innerH1 = document.createTextNode(item); 

  //

  

  //Add the text node to the newly created h1

  newH1.appendChild(innerH1);  

  //

  

  //Add the newly created element and its content into the DOM 

  document.body.insertBefore(newH1,document.body.secondChild);

  //

}



});

<button>Click me</button>

edited Nov 22 at 9:44

asked Nov 22 at 9:39

James Dean

604

Add }) to end of code
– Mohammad
Nov 22 at 9:43

What is your expected end result
– Nedko Dimitrov
Nov 22 at 9:43

secondChild isn’t a real thing. The rest looks OK
– Ben West
Nov 22 at 9:46

The problem is, that addEventListener expects a function reference/expression as the second argument, forEach returns undefined, hence no action is executed on a button click. Notice, that the iteration is executed immediately at the time you're attaching the listener.
– Teemu
Nov 22 at 9:50

add a comment |

This is my code

document.addEventListener('DOMContentLoaded',function(){



var numbers = [4, 9, 16, 25];



document.querySelector('button').addEventListener('click',numbers.forEach(myFunction))



function myFunction(item, index) {



  //create a new h1 element 

  var newH1 = document.createElement('h1'); 

  //

  

  //Insert content in the h1

  var innerH1 = document.createTextNode(item); 

  //

  

  //Add the text node to the newly created h1

  newH1.appendChild(innerH1);  

  //

  

  //Add the newly created element and its content into the DOM 

  document.body.insertBefore(newH1,document.body.secondChild);

  //

}



});

<button>Click me</button>

edited Nov 22 at 9:44

asked Nov 22 at 9:39

James Dean

604

Add }) to end of code
– Mohammad
Nov 22 at 9:43

What is your expected end result
– Nedko Dimitrov
Nov 22 at 9:43

secondChild isn’t a real thing. The rest looks OK
– Ben West
Nov 22 at 9:46

The problem is, that addEventListener expects a function reference/expression as the second argument, forEach returns undefined, hence no action is executed on a button click. Notice, that the iteration is executed immediately at the time you're attaching the listener.
– Teemu
Nov 22 at 9:50

add a comment |

This is my code

document.addEventListener('DOMContentLoaded',function(){



var numbers = [4, 9, 16, 25];



document.querySelector('button').addEventListener('click',numbers.forEach(myFunction))



function myFunction(item, index) {



  //create a new h1 element 

  var newH1 = document.createElement('h1'); 

  //

  

  //Insert content in the h1

  var innerH1 = document.createTextNode(item); 

  //

  

  //Add the text node to the newly created h1

  newH1.appendChild(innerH1);  

  //

  

  //Add the newly created element and its content into the DOM 

  document.body.insertBefore(newH1,document.body.secondChild);

  //

}



});

<button>Click me</button>

edited Nov 22 at 9:44

asked Nov 22 at 9:39

James Dean

604

This is my code

document.addEventListener('DOMContentLoaded',function(){



var numbers = [4, 9, 16, 25];



document.querySelector('button').addEventListener('click',numbers.forEach(myFunction))



function myFunction(item, index) {



  //create a new h1 element 

  var newH1 = document.createElement('h1'); 

  //

  

  //Insert content in the h1

  var innerH1 = document.createTextNode(item); 

  //

  

  //Add the text node to the newly created h1

  newH1.appendChild(innerH1);  

  //

  

  //Add the newly created element and its content into the DOM 

  document.body.insertBefore(newH1,document.body.secondChild);

  //

}



});

<button>Click me</button>

document.addEventListener('DOMContentLoaded',function(){



var numbers = [4, 9, 16, 25];



document.querySelector('button').addEventListener('click',numbers.forEach(myFunction))



function myFunction(item, index) {



  //create a new h1 element 

  var newH1 = document.createElement('h1'); 

  //

  

  //Insert content in the h1

  var innerH1 = document.createTextNode(item); 

  //

  

  //Add the text node to the newly created h1

  newH1.appendChild(innerH1);  

  //

  

  //Add the newly created element and its content into the DOM 

  document.body.insertBefore(newH1,document.body.secondChild);

  //

}



});

<button>Click me</button>

document.addEventListener('DOMContentLoaded',function(){



var numbers = [4, 9, 16, 25];



document.querySelector('button').addEventListener('click',numbers.forEach(myFunction))



function myFunction(item, index) {



  //create a new h1 element 

  var newH1 = document.createElement('h1'); 

  //

  

  //Insert content in the h1

  var innerH1 = document.createTextNode(item); 

  //

  

  //Add the text node to the newly created h1

  newH1.appendChild(innerH1);  

  //

  

  //Add the newly created element and its content into the DOM 

  document.body.insertBefore(newH1,document.body.secondChild);

  //

}



});

<button>Click me</button>

javascript

edited Nov 22 at 9:44

asked Nov 22 at 9:39

James Dean

604

edited Nov 22 at 9:44

asked Nov 22 at 9:39

James Dean

604

edited Nov 22 at 9:44

asked Nov 22 at 9:39

James Dean

604

asked Nov 22 at 9:39

James Dean

604

asked Nov 22 at 9:39

James Dean

604

Add }) to end of code
– Mohammad
Nov 22 at 9:43

What is your expected end result
– Nedko Dimitrov
Nov 22 at 9:43

secondChild isn’t a real thing. The rest looks OK
– Ben West
Nov 22 at 9:46

The problem is, that addEventListener expects a function reference/expression as the second argument, forEach returns undefined, hence no action is executed on a button click. Notice, that the iteration is executed immediately at the time you're attaching the listener.
– Teemu
Nov 22 at 9:50

add a comment |

Add }) to end of code
– Mohammad
Nov 22 at 9:43

What is your expected end result
– Nedko Dimitrov
Nov 22 at 9:43

secondChild isn’t a real thing. The rest looks OK
– Ben West
Nov 22 at 9:46

The problem is, that addEventListener expects a function reference/expression as the second argument, forEach returns undefined, hence no action is executed on a button click. Notice, that the iteration is executed immediately at the time you're attaching the listener.
– Teemu
Nov 22 at 9:50

Add }) to end of code
– Mohammad
Nov 22 at 9:43

What is your expected end result
– Nedko Dimitrov
Nov 22 at 9:43

secondChild isn’t a real thing. The rest looks OK
– Ben West
Nov 22 at 9:46

The problem is, that addEventListener expects a function reference/expression as the second argument, forEach returns undefined, hence no action is executed on a button click. Notice, that the iteration is executed immediately at the time you're attaching the listener.
– Teemu
Nov 22 at 9:50

add a comment |

1 Answer
1

active

oldest

votes

You could try to put numbers.forEach(myFunction); to a function inside the event, like this:

document.addEventListener('DOMContentLoaded', function () {



    var numbers = [4, 9, 16, 25];



    document.querySelector('button').addEventListener('click', function () {

        numbers.forEach(myFunction);

    });



    function myFunction(item, index) {



        //create a new h1 element 

        var newH1 = document.createElement('h1');

        //



        //Insert content in the h1

        var innerH1 = document.createTextNode(item);

        //



        //Add the text node to the newly created h1

        newH1.appendChild(innerH1);

        //



        //Add the newly created element and its content into the DOM 

        document.body.insertBefore(newH1, document.body.secondChild);

        //



    }



});

<button>Click me</button>

Syntax:

selector.addEventListener(event, function () {

    // implement...

});

answered Nov 22 at 9:43

Foo

add a comment |

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1 Answer
1

active

oldest

votes

1 Answer
1

active

oldest

votes

You could try to put numbers.forEach(myFunction); to a function inside the event, like this:

document.addEventListener('DOMContentLoaded', function () {



    var numbers = [4, 9, 16, 25];



    document.querySelector('button').addEventListener('click', function () {

        numbers.forEach(myFunction);

    });



    function myFunction(item, index) {



        //create a new h1 element 

        var newH1 = document.createElement('h1');

        //



        //Insert content in the h1

        var innerH1 = document.createTextNode(item);

        //



        //Add the text node to the newly created h1

        newH1.appendChild(innerH1);

        //



        //Add the newly created element and its content into the DOM 

        document.body.insertBefore(newH1, document.body.secondChild);

        //



    }



});

<button>Click me</button>

Syntax:

selector.addEventListener(event, function () {

    // implement...

});

answered Nov 22 at 9:43

Foo

add a comment |

You could try to put numbers.forEach(myFunction); to a function inside the event, like this:

document.addEventListener('DOMContentLoaded', function () {



    var numbers = [4, 9, 16, 25];



    document.querySelector('button').addEventListener('click', function () {

        numbers.forEach(myFunction);

    });



    function myFunction(item, index) {



        //create a new h1 element 

        var newH1 = document.createElement('h1');

        //



        //Insert content in the h1

        var innerH1 = document.createTextNode(item);

        //



        //Add the text node to the newly created h1

        newH1.appendChild(innerH1);

        //



        //Add the newly created element and its content into the DOM 

        document.body.insertBefore(newH1, document.body.secondChild);

        //



    }



});

<button>Click me</button>

Syntax:

selector.addEventListener(event, function () {

    // implement...

});

answered Nov 22 at 9:43

Foo

add a comment |

You could try to put numbers.forEach(myFunction); to a function inside the event, like this:

document.addEventListener('DOMContentLoaded', function () {



    var numbers = [4, 9, 16, 25];



    document.querySelector('button').addEventListener('click', function () {

        numbers.forEach(myFunction);

    });



    function myFunction(item, index) {



        //create a new h1 element 

        var newH1 = document.createElement('h1');

        //



        //Insert content in the h1

        var innerH1 = document.createTextNode(item);

        //



        //Add the text node to the newly created h1

        newH1.appendChild(innerH1);

        //



        //Add the newly created element and its content into the DOM 

        document.body.insertBefore(newH1, document.body.secondChild);

        //



    }



});

<button>Click me</button>

Syntax:

selector.addEventListener(event, function () {

    // implement...

});

answered Nov 22 at 9:43

Foo

You could try to put numbers.forEach(myFunction); to a function inside the event, like this:

document.addEventListener('DOMContentLoaded', function () {



    var numbers = [4, 9, 16, 25];



    document.querySelector('button').addEventListener('click', function () {

        numbers.forEach(myFunction);

    });



    function myFunction(item, index) {



        //create a new h1 element 

        var newH1 = document.createElement('h1');

        //



        //Insert content in the h1

        var innerH1 = document.createTextNode(item);

        //



        //Add the text node to the newly created h1

        newH1.appendChild(innerH1);

        //



        //Add the newly created element and its content into the DOM 

        document.body.insertBefore(newH1, document.body.secondChild);

        //



    }



});

<button>Click me</button>

Syntax:

selector.addEventListener(event, function () {

    // implement...

});

document.addEventListener('DOMContentLoaded', function () {



    var numbers = [4, 9, 16, 25];



    document.querySelector('button').addEventListener('click', function () {

        numbers.forEach(myFunction);

    });



    function myFunction(item, index) {



        //create a new h1 element 

        var newH1 = document.createElement('h1');

        //



        //Insert content in the h1

        var innerH1 = document.createTextNode(item);

        //



        //Add the text node to the newly created h1

        newH1.appendChild(innerH1);

        //



        //Add the newly created element and its content into the DOM 

        document.body.insertBefore(newH1, document.body.secondChild);

        //



    }



});

<button>Click me</button>

document.addEventListener('DOMContentLoaded', function () {



    var numbers = [4, 9, 16, 25];



    document.querySelector('button').addEventListener('click', function () {

        numbers.forEach(myFunction);

    });



    function myFunction(item, index) {



        //create a new h1 element 

        var newH1 = document.createElement('h1');

        //



        //Insert content in the h1

        var innerH1 = document.createTextNode(item);

        //



        //Add the text node to the newly created h1

        newH1.appendChild(innerH1);

        //



        //Add the newly created element and its content into the DOM 

        document.body.insertBefore(newH1, document.body.secondChild);

        //



    }



});

<button>Click me</button>

answered Nov 22 at 9:43

Foo

answered Nov 22 at 9:43

Foo

answered Nov 22 at 9:43

Foo

answered Nov 22 at 9:43

Foo

add a comment |

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