JAVASCRIPT

JavaScript arrays: combining and splitting

This series of articles mainly concentrates on working with JavaScript arrays. This is the second article in the series and mainly concentrates on working with arrays effectively. You can reuse these scripts for injection into server side controls easily (especially in .NET and Java).

Author Info:

By: Jagadish Chaterjee

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March 07, 2006

TABLE OF CONTENTS:

<html>
      <head>
            <meta name=vs_targetSchema content="http://schemas.microsoft.com/intellisense/ie5">
<script id="clientEventHandlersJS" language="javascript">
<!--
function Show()
{
      var salaryArray = [[2300, 3105, 2909, 4800],
                  [1800, 1940, 2470, 4350],
                  [900, 1200, 1923, 3810]];
    var arrayAsString =""
      for (var i = 0; i < salaryArray.length; i++) {
            arrayAsString += "<br>-----<br>" + salaryArray[i].join("<br>");
      }
      document.write(arrayAsString);
}

function ButtonShow_onclick() {
      Show();
}
//-->
            </script>
      </head>
      <body>
      <form id="form1">
                  <input type="button" value="Show" id="ButtonShow" name="ButtonShow" onclick="return ButtonShow_onclick()">
            </form>
      </body>
</html>

I shall explain the above code in the next section.

How to combine or join all elements available in a two-dimensional array using JavaScript: discussion

Within the code in the previous section, I mainly created a simple button (which is identified as “ButtonShow”). The button is defined with an “onclick” event which calls a JavaScript function, “ButtonShow_onclick.” The same function simply calls another JavaScript function named “Show.”

The function “Show” is defined as follows:

function eShow()
{
      var salaryArray = [[2300, 3105, 2909, 4800],
                  [1800, 1940, 2470, 4350],
                  [900, 1200, 1923, 3810]];
    var arrayAsString =""
      for (var i = 0; i < salaryArray.length; i++) {
            arrayAsString += "<br>-----<br>" + salaryArray[i].join("<br>");
      }
      document.write(arrayAsString);
}

The first statement creates a two-dimensional array named “salaryArray.” In this case, it is a direct declaration and initialization. For further details on this type of declaration, you can read through my first article of this series.

To hold the entire string of all values, I declared a new variable as follows:

var arrayAsString =""

Now, I need to go through all the single dimensional arrays present in “salaryArray.” For this, I tried to manage a loop as follows:

for (var i = 0; i < salaryArray.length; i++) {

Within the above statement, “salaryArray.length” gives the number of single dimensional arrays present in “salaryArray.” And I go through each of them starting at the 0th location (or index).

arrayAsString += "<br>-----<br>" + salaryArray[i].join("<br>");

Using the above statement, I combine (or join) each single dimensional array present in “salaryArray” and finally append (or add) to the variable “arrayAsString.” Just for the sake of clarity in output, I used <BR> tags during concatenation. You can learn by experimenting on it on your own (by, for instance, removing each <BR> tag and guessing the output).

I finally display the combined string using the following statement:

document.write(arrayAsString);

Next: How to split a string into an array using JavaScript >>