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                asp:Substitution control</td>
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                Substitution control is used to call a method that returns a string in an output-cached page.
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            <td colspan="2">&nbsp;</td>
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        Ideally Substitution control is used to call a method that returns a string in an output-cached page.
        Generally it is used when you want to cache a page but still want to return a dynamic string at a paricular part of the page.
        
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        There is one property that is used to return the dynamic string
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                    Used to assign method name that will fire each time page will load and return the string. Please note that this method will be a static method.
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        <!-- START - Demo Section -->
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                    DEMO : Substitution
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                    <a class="DemoShowSource" href="../../misc/codeviewer/default.aspx?pagename=~/tutorials/controls/substitution.aspx" target="_blank">Show Source Code</a>
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                    DateTime using Substitution: 
                    <asp:Substitution ID="Substitution1" runat="server" MethodName="WriteCurrentTimeDespiteThePageIsCahced" />
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                    DateTime using Cachced: 
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                    Notice that Cahced datetime will not change while Substituted datetime will change after each page refresh.
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                    <!-- START - Server Side Code -->
                    <pre>
// Substitution Control /////////////////////////////////////////
&lt;asp:Substitution ID="Substitution1" runat="server" MethodName="WriteCurrentTimeDespiteThePageIsCahced" /&gt;

 // Code Behind /////////////////////////////////////////
 protected static string WriteCurrentTimeDespiteThePageIsCahced(HttpContext context)
    {
        return DateTime.Now.ToString();
    }                    </pre> 
                    <!-- END - Server Side Code -->
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        <!-- END - Demo Section -->
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