button handler problem

[Newbie]

i have a c# asp.net webform that has a "Close" button. When the user clicks
the Close button, a message box saying "do u want to save to database...?".
the problem is that the statements inside the Close function are not being
executed. how can i save the data in the webform to the database? can i show
a message box without using javascript? can i call a function defined in the
code behind from within javascript? thanks in advance.

code behind:
private void Page_Load(objec t sender, System.EventArg s e)
{
//btnClose.Attrib utes.Add("OnCli ck", "javascript:Clo se()");
btnClose.Attrib utes.Add("OnMou seDown", "javascript:Clo se()");
.......
}

private void btnClose_Click( object sender, System.EventArg s e)
{
if (txtClose.Text == "1")
{

InsertToDatabas e();
}
Response.Redire ct("taskOrderSu mmary.aspx");
}

html code in aspx page:
<script type="text/javascript">
function Close(){
var agree=confirm(" Do you wish to save changes?");
if (agree)
{
document.Form1. txtClose.value = 1 ;
}
else
{
document.Form1. txtClose.value = 0 ;
}
}