JavaScript Array undefined

Undefined array is a condition that occurred when a user want to print an array element more than the declared size of element that an array object hold in it.

The Tutorial depicts an example from JavaScript Array Undefined. In this example we try to explain a code that makes you easy to understand ArrayUndefined.An array variable instantiate an array object, that hold the reference of elements indicated by array indexes[]. The for loop run and execute the script till variable i is less than array length. The document. write print the element in an array object that it hold.

In the same way, for loop execute the script and return you true till the variable i is less than array length. Incase the array length is more than the declared variable, then document. write print the undefined array on the browser.

JavaScriptArrayUndefined.html


<html>

  <head>

    <title>JavaScript Array undefined</title>

    <h1>JavaScript Array undefined</h1>

    <hr></hr>

    <script>

        var array=new Array();

        array[0]="Rose";

        array[1]="India";

        array[2]=".net";

        array[3]="Rohini";

         document.write("<b>"+"Array is: "+"</b>"+"<br>");

        for(i=0;i<array.length;i++){

            document.write(array[i]+"<br>");

        } 

    </script>

    <hr></hr>

    <script>

        document.write("<b>"+"Array Undefined is: "+"</b>"+"<br>");

        for(i=0;i<array.length;i++){

            document.write(array[5]+"<br>");

        }

    </script>

  </head>

  <body>

    </body>

</html>

Output of the program

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