Asp.Net textbox TextChanged event is not firing

Question

My code is 

 

<div class='input-group date datepicker'>

<asp:TextBox ID="txtdatefrom" OnTextChanged="txtdatefrom_TextChanged" AutoPostBack="true" runat="server" class="form-control dateHeight" placeholder="DD/MM/YYYY"></asp:TextBox>

<span class="input-group-addon bg-light datePadding">

<span class="icofont icofont-ui-calendar"></span>

</span>

</div>