The ImplicitResourceKey.Property property specifies the control property to be localized. The ImplicitResourceKey.Property property refers to the value after the first period (.) in an expression. For example, suppose you had an implicit resource in the following form:

<asp:label runat="server" id="label1" meta:resourcekey="Welcome"
        text="Welcome" 
        ie:text="Welcome Internet Explorer User"  
        forecolor="blue"/>  

This resource contains three keys, Welcome.Text, Ie:Welcome.Text, and Welcome.Forecolor, that potentially have localized resource values to retrieve from the resource file or source code. Those keys have ImplicitResourceKey.Property values of "Text", "Text", and "Forecolor", respectively.