C# - Reading Dynamically Generated HTML Element Value In Codebehind

I have an asp.net page where i have the below markup.Basically this markup is generated from codebehind by reading records from a table and looping thru them.For each record in table,there will be a div block. Basically this form is to read/show settings for a user.The settings entries are stored in a table.

<div id='divContainer' runat='server'>
<div id='div1' runat='server'>
<table>
<tr>
<th>Name</th>
<td><input type='text' id='txtName1' value='something' /></td>
</tr>
</table>
</div>
<div id='div2' runat='server'>
<table>
<tr>
<th>Domain name</th>
<td><input type='text' id='txtName2' value='something' /></td>
</tr>
</table>
</div>
<div id='div3' runat='server'>
<table>
<tr>
<th>URL</th>
<td><input type='text' id='txtName3' value='something' /></td>
</tr>
</table>
</div>
<div id='div4' runat='server'>
<table>
<tr>
<th>Some other value is enabled ?</th>
<td><input type='checkbox' id='chk4' /></td>
</tr>
</table>
</div>
</div>

The id's of each input element will be unique. Now in codebehind i want to read the values of each input elment to save the changes user made.How can i read the elements here ? Since the mark up is generated in codebehind as a string and appended the the INNER HTML of the external div,I cant read values like we do for a control which we drag and drop in the IDE.