How to get full ClientID for a control from server side code
<p>I have a <code>TextBox</code> inside <code>ItemTemplate</code> of a <code>Repeater</code> that is also inside a <code>ItemTemplate</code>. </p>

<p>Server side I have:</p>

<pre><code>protected void txtValorMaterialAsign_TextChanged(object sender, EventArgs e)
{
    string controlId = ((TextBox)sender).ClientID;
}
</code></pre>

<p>wich result in: </p>

<p><code>rptFilasDeUnMaterial_ctl04_txtValorMaterialAsign</code></p>

<p>But client side the Id for that control is (according to Chrome's F12):</p>

<pre><code>ctl00_contenido_wucMateriales_rptMateriales_ctl00_rptFilasDeUnMaterial_ctl01_txtValorMaterialAsign
</code></pre>

<p>How can I get the full Id from server side code?</p>
