A potentially dangerous Request.Form value was detected from the client

For .net 4.0 if you get the above error you have to add
<httpRuntime requestValidationMode="2.0" />
Inside the <system.web> tags and

ValidateRequest="false" in <Page> directive of .aspx page

Oracle cache dependency in asp.net

private DataSet bindCachedData()
{
string sql = "SELECT * FROM np_pucm_refresh_cal";
constr = "user id=NPUSER;data source=PNPSCAL;password=NPUSER;Min Pool
Size=1;Connection Lifetime=0;Connection Timeout=60;Incr Pool
Size=1;Decr Pool Size=1;";
DataSet ds;
ds = (DataSet)Cache.Get("UserTable");

if (ds ==null)
{
lblMsg.Text = "Data fetched from Table";
using (OracleConnection con = new OracleConnection(constr))
{
con.Open();

using (OracleCommand cmd = new OracleCommand(sql, con))
{
OracleDependency dep = new OracleDependency(cmd);
cmd.Notification.IsNotifiedOnce = false;
dep.OnChange += new OnChangeEventHandler(OnMyNotificaton);

OracleDataAdapter da = new OracleDataAdapter(cmd);
ds = new DataSet();
da.Fill(ds);

Cache.Insert("UserTable", ds);
}
}
}
else
lblMsg.Text = "Data fetched from Cache";

return ds;
}

public void OnMyNotificaton(object src, OracleNotificationEventArgs arg)
{
DataTable changeDetails = arg.Details;
Cache.Remove("UserTable");
lblMsg.Text = "Data fetched from Table";
}

protected void Timer1_Tick(object sender, EventArgs e)
{
GridView1.DataSource = bindCachedData();
GridView1.DataBind();
}

Import a div's content into excel using javascript

Call the bellow js function "OnClientClick" event of a button

<script language="javascript" type="text/javascript">
function ABC() {
var strCopy = document.getElementById('calendar').innerHTML;
window.clipboardData.setData("Text", strCopy);
var objExcel = new ActiveXObject("Excel.Application");
objExcel.visible = true;

var objWorkbook = objExcel.Workbooks.Add;
var objWorksheet = objWorkbook.Worksheets(1);
objWorksheet.Paste;

return false;
}
</script>

Create a Win Form with curved corners

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;

namespace SampleFormApplication
{
public partial class Login : Form
{
[DllImport("Gdi32.dll", EntryPoint = "CreateRoundRectRgn")]
private static extern IntPtr CreateRoundRectRgn
(
int nLeftRect,
int nTopRect,
int nRightRect,
int nBottomRect,
int nWidthEllipse,
int nHeightEllipse
);

public Login()
{
InitializeComponent();
this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.None;
Region = System.Drawing.Region.FromHrgn(CreateRoundRectRgn(0, 0, Width - 10, Height - 10, 50, 50));
}

private void button1_Click(object sender, EventArgs e)
{
this.Close();
}
}
}