span id value

Question

How can i save the span id value in .cs file?

 

 My code:

<div class="col-lg-5 pull-left" style="float: left; margin-left: -15px;">
<ul class="breadcrumb">
<li class="active">Create Model:
<%--<asp:Label ID="lblSystem" runat="server"></asp:Label>--%>
<span id="lblSystem" style="color: #000; font-size: 14px; font-weight: bold;"></span>
<input id="txt" type="text" />
</li>
</ul>
</div> 

 

i want to save "lblSystem"  value.any ine help me.......

 

Thanks in advance.....