did you add the control to the Controls collection? for example<form id="form1" runat="server">
...
<asp:PlaceHolder id="ph" runat="server" />
</form>ph.Controls.Add(call);
...
<asp:PlaceHolder id="ph" runat="server" />
</form>ph.Controls.Add(call);
cal1.Height=60;
cal1.Width=160;
cal1.ShowDayHeader=false;
cal1.SelectedDate=DateTime.Now;
cal1.SelectedDayStyle.BackColor=Color.Blue;
this.PlaceHolder1.Controls.Add(cal1);
tc2.Controls.Add(cal1); TableRow tr=new TableRow();
tr.Cells.Add(tc2);
Table1.Rows.Add(tr);运行时能正常显示出日历控件,点击时选中日期背景也能变成蓝色。但就是不能在初始显示时使所指定的日期背景为蓝。