How to call a function from markup page that includes data-binding in ASP.NET

How to call a function in ASP.NET
In Mark Up Page :

<%# GetGreeting(Eval("FullName").ToString()) %>

In code behind :
protected string GetGreeting(string name)
{
if (String.IsNullOrEmpty(name))
{
return "Hello";
}
else
{
return "Hello " + name;
}
}