send a parameter to Crystal report in webform application

[Simon]

Hi,
I am using ASP.NET with C# and Crystal Report. I have a textbox et
a asp.net button. I send a number in the texte, I push the button and
I want to see the report with value related to the number in the
textbox. The problem is that I need to call the crystal report
function in the "override protected void OnInit(EventArg s e)" function
to see my graphic and picture in the report. When I push the button,
the content of the textbox is not filled yet in the OnInit... how can
I send parameters to crystal report if I must use the OnInit ? Page
load is too late...
my crystal report function looks like that (where txtIDPaquet.Tex t is
the name of the parameter field..):
crFunction()
{
mReportDocument = new ReportDocument( );
mReportDocument .Load(Server.Ma pPath("\\" + Request.Applica tionPath) +
"\\" + CST.PREFIXE_RAP PORTS + CST.FICHIER_RAP PORT_HISTORIQUE _PAQUET);
crystalView.Sel ectionFormula = "{TablePaquets. ID} = " +
txtIDPaquet.Tex t;
this.crystalToo lBar.Visible = true;
this.crystalVie w.Visible = true;
lblMessageErreu r.Visible = false;
crystalView.Rep ortSource = mReportDocument ;
crystalToolBar. activeCrystalTo olBar(mReportDo cument,crystalV iew);
}
thank you!