<div>
This may need to be refined a bit for your exact situation (for example staying within the current content block if needed?) but here is an example using a simple master page and a webform using it. 
 
In the master page I added this javascript in the head section: 

<pre><code class="code-10 nolinks" id="code-20-41385702-1"> &lt;script type=&quot;text/javascript&quot;&gt;
 function listTextboxes() {
 var frm = document.forms['form1'], // name of form in master page
 log = document.getElementById('&lt;%= TextBox1.ClientID %&gt;'),
 idx,
 fld;

 log.value = '';
 for (idx = 0; idx &lt; frm.elements.length; idx++) {
 fld = frm.elements[idx];
 if (fld.id != log.id &amp;&amp; (fld.tagName == 'TEXTAREA' || (fld.tagName == 'INPUT' &amp;&amp; fld.type == 'text'))) {
 log.value += fld.id + ' / ' + fld.name + ' : &quot;' + escape(fld.value) + '&quot;\n';
 }
 }
 }
 &lt;/script&gt;
</code></pre>
also added these controls in the master page for testing: 

<pre><code class="code-1 nolinks" id="code-20-41385702-2"> &lt;asp:Button ID=&quot;Button1&quot; runat=&quot;server&quot; Text=&quot;List text boxes&quot; UseSubmitBehavior=&quot;False&quot; OnClientClick=&quot;listTextboxes()&quot; /&gt;&lt;br /&gt;&lt;br /&gt;
 &lt;asp:TextBox ID=&quot;TextBox1&quot; runat=&quot;server&quot; TextMode=&quot;MultiLine&quot; Rows=&quot;5&quot; Columns=&quot;70&quot;&gt;&lt;/asp:TextBox&gt;
</code></pre>
Then just some random controls in the ContentPlaceHolder on the actual page: 

<pre><code class="code-1 nolinks" id="code-20-41385702-3"> &lt;asp:TextBox ID=&quot;TextBox1&quot; runat=&quot;server&quot;&gt;t1&lt;/asp:TextBox&gt;&lt;br /&gt;&lt;br /&gt;
 &lt;asp:TextBox ID=&quot;TextBox2&quot; runat=&quot;server&quot; Columns=&quot;30&quot;&gt;t2&lt;/asp:TextBox&gt;&lt;br /&gt;&lt;br /&gt;
 &lt;asp:TextBox ID=&quot;TextBox3&quot; runat=&quot;server&quot; TextMode=&quot;MultiLine&quot; Rows=&quot;3&quot; Columns=&quot;70&quot;&gt;t3&lt;/asp:TextBox&gt;&lt;br /&gt;&lt;br /&gt;
 &lt;asp:TextBox ID=&quot;TextBox4&quot; runat=&quot;server&quot; TextMode=&quot;MultiLine&quot; Rows=&quot;4&quot; Columns=&quot;50&quot;&gt;t4&lt;/asp:TextBox&gt;&lt;br /&gt;&lt;br /&gt;
</code></pre>
The javascript code logs the id, name and value of the textboxes (which translate to text inputs and textareas) in a separate textbox.
</div>

<div>
This may need to be refined a bit for your exact situation (for example staying within the current content block if needed?) but here is an example using a simple master page and a webform using it. 
 
In the master page I added this javascript in the head section: 

<pre><code class="code-10 nolinks" id="code-20-41385704-1"> &lt;script type=&quot;text/javascript&quot;&gt;
 function listTextboxes() {
 var frm = document.forms['form1'], // name of form in master page
 log = document.getElementById('&lt;%= TextBox1.ClientID %&gt;'),
 idx,
 fld;

 log.value = '';
 for (idx = 0; idx &lt; frm.elements.length; idx++) {
 fld = frm.elements[idx];
 if (fld.id != log.id &amp;&amp; (fld.tagName == 'TEXTAREA' || (fld.tagName == 'INPUT' &amp;&amp; fld.type == 'text'))) {
 log.value += fld.id + ' / ' + fld.name + ' : &quot;' + escape(fld.value) + '&quot;\n';
 }
 }
 }
 &lt;/script&gt;
</code></pre>
also added these controls in the master page for testing: 

<pre><code class="code-1 nolinks" id="code-20-41385704-2"> &lt;asp:Button ID=&quot;Button1&quot; runat=&quot;server&quot; Text=&quot;List text boxes&quot; UseSubmitBehavior=&quot;False&quot; OnClientClick=&quot;listTextboxes()&quot; /&gt;&lt;br /&gt;&lt;br /&gt;
 &lt;asp:TextBox ID=&quot;TextBox1&quot; runat=&quot;server&quot; TextMode=&quot;MultiLine&quot; Rows=&quot;5&quot; Columns=&quot;70&quot;&gt;&lt;/asp:TextBox&gt;
</code></pre>
Then just some random controls in the ContentPlaceHolder on the actual page: 

<pre><code class="code-1 nolinks" id="code-20-41385704-3"> &lt;asp:TextBox ID=&quot;TextBox1&quot; runat=&quot;server&quot;&gt;t1&lt;/asp:TextBox&gt;&lt;br /&gt;&lt;br /&gt;
 &lt;asp:TextBox ID=&quot;TextBox2&quot; runat=&quot;server&quot; Columns=&quot;30&quot;&gt;t2&lt;/asp:TextBox&gt;&lt;br /&gt;&lt;br /&gt;
 &lt;asp:TextBox ID=&quot;TextBox3&quot; runat=&quot;server&quot; TextMode=&quot;MultiLine&quot; Rows=&quot;3&quot; Columns=&quot;70&quot;&gt;t3&lt;/asp:TextBox&gt;&lt;br /&gt;&lt;br /&gt;
 &lt;asp:TextBox ID=&quot;TextBox4&quot; runat=&quot;server&quot; TextMode=&quot;MultiLine&quot; Rows=&quot;4&quot; Columns=&quot;50&quot;&gt;t4&lt;/asp:TextBox&gt;&lt;br /&gt;&lt;br /&gt;
</code></pre>
The javascript code logs the id, name and value of the textboxes (which translate to text inputs and textareas) in a separate textbox. 
<a href="https://filedb.experts-exchange.com/incoming/2015/12_w52/1060662/capture.png" target="_blank" title="capture of output (20 KB)"><img alt="capture of output" class="file-block lazyload" style="max-width: 618px;" data-src="https://filedb.experts-exchange.com/incoming/2015/12_w52/1060662/capture.png" /></a>
</div>

capture.png

<div>
Does it make a diff to have the button and the log text area control on child page itself??
</div>

<div>
I've requested that this question be closed as follows: 
 
Accepted answer: 0 points for flyhighrohit12's comment <a href="https://www.experts-exchange.com/questions/28905260/content-page-control-looping.html?anchorAnswerId=41385727#a41385727" rel="ugc">#a41385727</a> 
 
for the following reason: 
 
Thanks
</div>

<div>
Looks like wrong comment selected as solution.
</div>

<div>
<div class="content wysiwyg-content">
hi experts, 
 
I have a content page within a master page.It has few textboxes and text areas which I need to iterate through,I want this iteration via javascript.How to achieve it?
</div>
</div>

hi experts,

I have a content page within a master page.It has few textboxes and text areas which I need to iterate through,I want this iteration via javascript.How to achieve it?

content page control looping

JavaScript is a dynamic, object-based language commonly used for client-side scripting in web browsers. Recently, server side JavaScript frameworks have also emerged. JavaScript runs on nearly every operating system and  in almost every mainstream web browser.

JavaScript

The .NET Framework is not specific to any one programming language; rather, it includes a library of functions that allows developers to rapidly build applications. Several supported languages include C#, VB.NET, C++ or ASP.NET.

.NET Programming

C# is an object-oriented programming language created in conjunction with Microsoft’s .NET framework. Compilation is usually done into the Microsoft Intermediate Language (MSIL), which is then JIT-compiled to native code (and cached) during execution in the Common Language Runtime (CLR).

The successor to Active Server Pages, ASP.NET websites utilize the .NET framework to produce dynamic, data and content-driven web applications and services. ASP.NET code can be written using any .NET supported language. As of 2009, ASP.NET can also apply the Model-View-Controller (MVC) pattern to web applications