Restrict Duplicate Record Insertion On Page Refresh

The two ways which I believe is pretty simple to prevent duplicate record insertion on page refresh.

1. Using ViewState and Session


public partial class _Default : System.Web.UI.Page
{
private bool _refreshState;
private bool _isRefresh;
public bool IsRefresh
{
get
{
return _isRefresh;
}
}
protected override void LoadViewState(object savedState)
{
object[] allStates = (object[])savedState;
base.LoadViewState(allStates[0]);
_refreshState = (bool)allStates[1];
_isRefresh = _refreshState == (bool)Session["__ISREFRESH"];
}

protected override object SaveViewState()
{
Session["__ISREFRESH"] = _refreshState;
object[] allStates = new object[2];
allStates[0] = base.SaveViewState();
allStates[1] = !_refreshState;
return allStates;
}

protected void Button2_Click(object sender, EventArgs e)
{
if(!IsRefresh)
Response.Write("Thanx for visiting");
}
}




2. Use Response.Redirect

public partial class _Default : System.Web.UI.Page
{

protected void Page_Load(object sender, EventArgs e)
{
Boolean blnRefreshed = true;
}
protected void Button1_Click(object sender, EventArgs e)
{
//code to save your data here
Response.Redirect("default.aspx");
}

}


The second one has a performance overhead. Let’s check how.
Put break point on Page_Load and click on button. The break points on Page_Load will be hit twice intead of one due to Response.Redirect, the second hit is overhead.

The second hit can be avoided by using the first method.

Happy Coding :)