Button Control dynamic text

I have a button and the text shuold be dynamic(call a function and return a string).
<asp:LinkButton ID="LinkButton1" runat="server" Text='<%= GetString() %>' OnClick="LinkButton1_Click"></asp:LinkButton>  
In cs file,
public string GetString(){
return "Submit";
}
 
The above case, GetString() has been ignored.
Instead of writing code on Page_Load event >> LinkButton1.Text = GetString();
Can i write it in the aspx page?
 
Thanks all !

 
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