Can I configure a SQLDataSource object to use.....

.. the Membership ProviderUserKey value as the parameter of a stored procedure ?

It seems obvious to me that you would want to do this, but I can only see that it allows you to pass Profile parameters.

You can pass any value as a parameter. It has some built-in parameter types, such as ProfileParameter, FormParameter, ControlParameter etc, but you can just use <asp:Parameter>. Beyond the most basic of usage, the SqlDataSource isn't the most intuitive of controls, I'm afraid. This should help you unpick it a bit though:http://aspnet.4guysfromrolla.com/articles/030106-1.aspx

|||You can always write your own parameter:

1using System;2using System.ComponentModel;3using System.Globalization;4using System.Web;5using System.Web.Security;6using System.Web.UI;7using System.Web.UI.WebControls;89public class MembershipParameter : Parameter10{11public MembershipParameter(string name, TypeCode typeCode,string propertyName) :base(name, typeCode)12 {13this.PropertyName = propertyName;14 }1516public MembershipParameter(string name,string propertyName) :base(name)17 {18this.PropertyName = propertyName;19 }2021public MembershipParameter()22 {23 }2425protected MembershipParameter(MembershipParameter original) :base(original)26 {27if (null == original)throw new ArgumentNullException("original");28this.PropertyName = original.PropertyName;29 }3031public string PropertyName32 {33get34 {35object value = ViewState["PropertyName"];36if (null !=value)return (string)value;37return string.Empty;38 }39set40 {41if (null !=value && 0 ==value.Length)value =null;42if (!string.Equals(value, (string)ViewState["PropertyName"], StringComparison.OrdinalIgnoreCase))43 {44 ViewState["PropertyName"] =value;45 OnParameterChanged();46 }47 }48 }4950protected override Parameter Clone()51 {52return new MembershipParameter(this);53 }5455protected override object Evaluate(HttpContext context, Control control)56 {57object result =null;58string prop =this.PropertyName;59if (!string.IsNullOrEmpty(prop))60 {61 MembershipUser user = Membership.GetUser();62if (null != user)63 {64 result = DataBinder.Eval(user, prop);65 }66 }6768return result;69 }70}