dynamic Checkbox issue

[mobins]

i create dynamic checkboxes in coloum of table(<td id="trial" runat="server"></td>) from selecting quantity from dropdwonlist. well creating dynmic checkbox is not an issue.. well the issue is tht i am not able to check whether the Checkboxes is checked or not on a Button click.... the functiion used for generating dyamic checkbox.. protected void ddlList_SelectedIndexChanged(object sender, EventArgs e) { int no=convert.toint32(ddlist.selectedvalue); for(int i=1;i=<no;i++) { checkbox ch=new checkbox() ch.ID="chk_t"+i; ch.text="trl" trial.controls.add(ch); } } the function where i check whether checkboxes is checked protected void btnSave_Click(object sender, EventArgs e) { list<string> status_tn=new list<string>(); for (int j = 1; j <= no; j++) { trialid = "chk_t" + j; CheckBox checks=(CheckBox)trial.FindControl(trialid); if (checks.Checked) { status_tn.Add("Trial"); } } } in this function i get error : :System.NullReferenceException was unhandled by user code Message="Object reference not set to an instance of an object." Source="App_Web_pm_-zh7o" StackTrace: at btn_save_Click(Object sender, EventArgs e) in d:\Dot Net App\Talents\types_seeb.aspx.cs:line 325 at System.Web.UI.WebControls.Button.OnClick(EventArgs e) at System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) at System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) at System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) at System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)

[Satish_S]

i realize when page get posts check box not generating dynamically so try to re generate the dynamic check boxes in your save click, sorry if i am wrong

protected void btnSave_Click(object sender, EventArgs e)
{

ddlList_SelectedIndexChanged(sender,e)

/*your save functionality*/

}

[raju melveetilpurayil]

mobins wrote:

CheckBox checks=(CheckBox)trial.FindControl(trialid); if (checks.Checked) { status_tn.Add("Trial"); }

//to solve error

CheckBox checks=(CheckBox)trial.FindControl(trialid);
if(checks!=null)
{
if (checks.Checked)
{
status_tn.Add("Trial");
}
}

[Rajendra Prasad Panchati]

Hi, Before Checking the status of check boxes whether they are checked or not, Please Confirm that control is exists or not. And also confirm that the dynamical checkboxes generation code is not executed on button click event. I hope u understand it :thumbsup:...

Rajendra Prasad Panchati .Net/Sharepoint Software Enginner hyderabad.