Using Calendar Control in ASP.NET

The Database Data is stored as:

To begin with User Interface Drag and drop

• Calendar Control
• DataGrid

<asp:Calendar id="Calendar1" OnDayRender="CalendarDRender" runat="server" 
	BorderWidth="1px" NextPrevFormat="FullMonth" BackColor="White" Width="350px"
                 ForeColor="Black" Height="190px" 
	Font-Size="9pt" Font-Names="Verdana" BorderColor="White">
	<TodayDayStyle BackColor="#CCCCCC"></TodayDayStyle>
	<NextPrevStyle Font-Size="8pt" Font-Bold="True" ForeColor="#333333" VerticalAlign="Bottom">
                 </NextPrevStyle>
	<DayHeaderStyle Font-Size="8pt" Font-Bold="True"></DayHeaderStyle>
	<SelectedDayStyle ForeColor="White" BackColor="#333399"></SelectedDayStyle>
	<TitleStyle Font-Size="12pt" Font-Bold="True" BorderWidth="4px" ForeColor="#333399" 
               BorderColor="Black" BackColor="White"></TitleStyle>
	<OtherMonthDayStyle ForeColor="#999999"></OtherMonthDayStyle>
</asp:Calendar>
<asp:DataGrid id="DataGrid1" style="Z-INDEX: 102; LEFT: 23px; POSITION: absolute; TOP: 271px" 
	runat="server" Font-Size="XX-Small" Font-Names="Verdana" Visible="False">
</asp:DataGrid>

Now our code. :

In Page_Load

• Fill the DataSet

In Calendar1_PreRender

• Check for it the Date is from OtherMonth 
• Navigate through the DataSet if Date is not from other month
• Check if the date is null
• If not Set the BackColor for the Date based on the value in the DataBase

In Calendar1_SelectionChanged

• Based on the date Selected in the Calendar Control display the Data in the Datagrid.

C#
SqlConnection mycn;
SqlDataAdapter myda;
DataSet ds = new DataSet ();
DataSet dsSelDate;
String strConn;
private void Page_Load(object sender, System.EventArgs e)
{
	// Put user code to initialize the page here
	strConn="Data Source=localhost;uid=sa;pwd=;Initial Catalog=northwind";
	mycn = new SqlConnection(strConn);
	myda = new SqlDataAdapter ("Select * FROM EventsTable", mycn);
	myda.Fill (ds,"Table");
}

protected void CalendarDRender(object  sender  ,System.Web.UI.WebControls.DayRenderEventArgs  e  ) 
{
	// If the month is CurrentMonth
	if (! e.Day.IsOtherMonth )
	{
	foreach (DataRow dr in ds.Tables[0].Rows)
	{
		if ((dr["EventDate"].ToString() != DBNull.Value.ToString()))
		{
			DateTime dtEvent= (DateTime)dr["EventDate"];
			if (dtEvent.Equals(e.Day.Date))
			{
				e.Cell.BackColor = Color.PaleVioletRed;
			}
		}
	}	
	}
		//If the month is not CurrentMonth then hide the Dates
	else
	{
		e.Cell.Text = "";
	}
}

private void Calendar1_SelectionChanged(object sender, System.EventArgs e)
{
	myda = new SqlDataAdapter("Select * from EventsTable where EventDate='" + 
		Calendar1.SelectedDate.ToString() + "'", mycn);
	dsSelDate = new DataSet();
	myda.Fill(dsSelDate, "AllTables");
	if (dsSelDate.Tables[0].Rows.Count == 0 )
	{
		DataGrid1.Visible = false;
	}
	else
	{
		DataGrid1.Visible = true;
		DataGrid1.DataSource = dsSelDate;
		DataGrid1.DataBind (); 
	}
}					
VB.NET
Dim myconnection As SqlConnection
Dim myda As SqlDataAdapter
Dim ds As New DataSet()
Dim dsSelDate As DataSet
Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
	myconnection = New SqlConnection("Server=localhost;uid=sa;password=;database=northwind;")	
	myda = New SqlDataAdapter("Select * from EventsTable", myconnection)
	myda.Fill(ds, "AllTables")
End Sub

Protected Sub CalendarDRender(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.DayRenderEventArgs)
	'If the month is CurrentMonth
	If Not e.Day.IsOtherMonth Then
	Dim dr As DataRow
	For Each dr In ds.Tables(0).Rows
	'If EventDate is not Null
	If Not dr("EventDate") Is DBNull.Value Then
		Dim dtEvent As DateTime = dr("EventDate").ToString
		'If EventDate =CalendarDate
		If dtEvent.Equals(e.Day.Date) Then
			e.Cell.BackColor = Color.PaleVioletRed
		End If
	End If
	Next
	'If the month is not CurrentMonth then hide the Dates
	Else
		e.Cell.Text = ""
	End If
End Sub

Private Sub Calendar1_SelectionChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) _
	 Handles Calendar1.SelectionChanged
	myda = New SqlDataAdapter("Select * from EventsTable where EventDate='" & _
		Calendar1.SelectedDate.ToString & "'", myconnection)
	dsSelDate = New DataSet()
	myda.Fill(dsSelDate, "AllTables")
	If dsSelDate.Tables(0).Rows.Count = 0 Then
		DataGrid1.Visible = False
	Else
		DataGrid1.Visible = True
		DataGrid1.DataSource = dsSelDate
		DataGrid1.DataBind()
	End If
End Sub

The Output of this code: