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DataGridViewComboBoxCell failing to retain choice, auto-selecting item at '0' th index of collection

As clear from the title, my datagridviewComboboxCell, which I am adding to selected cells only, are showing it's dropdown list perfectly, and I can select them seamlessly. Problem arises when the combobox losses focus, it forgets everything about selected item and auto selects the item at index 0, of it's range collection. And many time, a 'DataGridViewDataErrorEvent' is occuring(I traced it by adding DataError event handler). I can not understand what is going wrong to cause the error to fire. Moreover even though I daclare
e.Cancel = false;
in the eventhandler, the ComboBox auto-selects item at index 0.
Plese help me out of this.
N.B . I forgot to add initially(when it appears to screen!), the DataGridViewComboBox has no item selected.
EDIT:-
Code snippet
//Creating and Adding propertiesof DataGridViewComboBoxCell.
RegViewdataGridView.Rows[uniqcustCount].Cells[day].ReadOnly = false; //uniqcustCount & day Are Integers
var pcmbcell = new DataGridViewComboBoxCell();
var tcmbcell = new DataGridViewComboBoxCell();
RegViewdataGridView[day,uniqcustCount] = pcmbcell;
pcmbcell.ReadOnly = false;
pcmbcell.DropDownWidth = 80;
pcmbcell.DataSource = shipdPrdLst;
pcmbcell.DisplayStyle = DataGridViewComboBoxDisplayStyle.ComboBox;
RegViewdataGridView.DataError += RegViewdataGridView_DataError;
void RegViewdataGridView_DataError(object sender, DataGridViewDataErrorEventArgs e)
{
e.Cancel = false;
}

asp.net drop down list duplicated itself when post back

It is a very weird problem
when I change the value of the drop down list, a new drop down list is show. I am so confused,
To know what I am talking about, please check these images.
edit
code for bind
CallerId = Request["CallerID"];
if (String.IsNullOrWhiteSpace(CallerId)) return;
var results = ZumaDa.GetCustomerInformation(CallerId);
rowCount = results.Rows.Count;
CallerId = rowCount > 0 ? results.Rows[0][4].ToString() : CallerId;
if (rowCount > 1)
{
ListView1.Enabled = false;
GridView1.DataSource = results;
GridView1.DataBind();
}
else
{
GridView1.Enabled = false;
ListView1.DataSource = results;
ListView1.DataBind();
}
That code is in page load and NOT on !ispostback

Since you updated your question with the ListView markup, and your Page_Load code, it appears the problem of the duplicated DropDownList goes away after you wrap your databinding code in an if (!Page.IsPostBack) block.
One problem in your code is that, in your SelectedIndexChanged event, you're searching the ListView for your DropDownList and TextBox. You need to search the ListViewItem control where the SelectedIndexChanged event occurred.
To do that, you can first get the DropDownList from the "sender" parameter. Then you should find the "NamingContainer" control of the DropDownList, and search that. Like this:
var dropDown = (DropDownList)sender;
var visitID = (TextBox)dropDown.NamingContainer.FindControl("visitID");
That second line of code might need to have an additional ".NamingContainer" depending on your markup.

I think you need to bind listview in !IsPostback check means when do postback it pageload event fired and it bind dropdown with second time or if its not please share binding code

Preserving (dynamically populated) dropdownlist items and selection inside of GView

I have a column in a GridView which has a Dropdownlist in the EditTemplate
The data for this dropdownlist is added dynamically (items.add()) after the user enters the edit mode for that row.
foreach (var bgElement in userCropList.FirstOrDefault(c => c.Crop == cropToBeUpdated).BGs)
{
ddl.Items.Add(bgElement.BG);
}
ddl.SelectedIndex = userCropList.FirstOrDefault(c => c.Crop == cropToBeUpdated).BGs.FindIndex(d => d.Default == true);
When the user clicks the update button to save his changes, the page does a postback and as such lose the items aswell as the selectedindex which i need for the following bit in the RowUpdating event.
DropDownList ddl = (DropDownList)GVCrops.Rows[e.RowIndex].FindControl("ddlAvailableBGs");
updatedCrop.BGs.FirstOrDefault(c => c.BG == ddl.SelectedValue).Default = true;
What came to my mind was to put the value the user selects in a viewstate variable and read from it in the RowUpdating event.
I am asking if there is an easier (not that it is hard) or already available thing that I am missing which could that for me?
Edit:
Ok, turns out my method ..
RowEditing():
ViewState.Add("SelectedBGIndex", ddl.SelectedValue);
RowUpdating():
if (ViewState["SelectedBGIndex"] != null)
{
updatedCrop.BGs.FirstOrDefault(c => c.BG == ViewState["SelectedBGIndex"].ToString()).Default = true;
}
..is not going to work for the same reason apparently.
When the user clicks the update button for the row it will post back and the drop down list is reset with no selection and no items inside.
Seems like the solution would be a JavaScript function.
Any thoughts how to approach it?

How to get values of textbox and dropdownlist controls in a gridview on a button click event?

On the page load there will be gridview with a default row....there is a button with a + sign at the bottom...on the button click i want to create a new rows in the grid..before that i need to make sure that all fields have values.But I am getting null values..
My code is:
TextBox name_value = ((TextBox)Gridview1.Rows[0].FindControl("TextBox1"));
TextBox age_value = ((TextBox)Gridview1.Rows[0].FindControl("TextBox2"));
DropDownList sex_value = ((DropDownList)Gridview1.Rows[0].FindControl("DropDownList1"));
DropDownList berth_value = ((DropDownList)Gridview1.Rows[0].FindControl("DropDownList2"));
Any help will be appreciated.

Please write this code at end of the code
Gridview1.EditIndex-1 not sure EditIndex or Edititemindex please try it may be help you.

Try using a condition
if(name_value.Text!="" && age_value.Text && sex_value.Text && berth_value.Text)
{
//action
}

DropdownList.selectedIndex always 0 (yes, I do have !isPostBack)

(Scroll down to bottom of post to find solution.)
Got a asp.net page which contains a
Datalist. Inside this datalist, there
is a template containing a
dropdownlist and each time the
datalist is filled with an item, a
ItemCreatedCommand is called. The
itemCreatedCommand is responsible for
databinding the dropdownlist.
I think the problem lies here, that
I'm using ItemCreatedCommand to
populate it - but the strange things
is that if I choose the color "green",
the page will autopostback, and I will
see that the dropdown is still on the
color green, but when trying to use
it's SelectedIndex, I always get 0...
protected void DataListProducts_ItemCreatedCommand(object
source, DataListItemEventArgs e)
var itemId = (String)DataListProducts.DataKeys[e.Item.ItemIndex];
var item = itemBLL.GetFullItem(itemId);
var DropDownListColor = (DropDownList)e.Item.FindControl("DropDownListColor");
//Also tried with :
//if(!isPostBack) {
DropDownListColor.DataSource = item.ColorList;
DropDownList.Color.Databind();
// } End !isPostBack)
Label1.test = DropDownListColor.SelectedIndex.toString();
// <- THIS IS ALWAYS 0! *grr*
I've narrowed down the code a bit for
viewing, but still you can see what
I'm trying to do :) The reason for
why I'm doing this, and not declaring
the datasource for the colors directly
i aspx-page, is that I need to run a
test if(showColors), but I do not want
to clutter up the html-page with code
that I feel should be in the code
behind-file.
EDIT: After trying to alter
SelectedIndexChange - I'm having a
"logical" confusion in my head now -
how am I to alter elements inside the
datalist? Since, as far as I know - I
do not have any way to check which of
the items in the datalist this
particular dropdownlist belongs to...
Or? I'm going to try out a few ways
and see what I end up with ;) But do
please post your thoughts on this
question :)
SOLUTION:
Either bubble the event to ItemCommand, or Handle the event, get the senders parent(which is a datalistItem and manipulate elements in there.
protected void DropDownListColor_SelectedIndexChanged(object sender, EventArgs e)
{
DropDownList dropDownListColor = (DropDownList)sender;
DataListItem dataListItem = (DataListItem)dropDownListColor.Parent;
var item = items[dataListItem.ItemIndex];
var color = item.ItemColor[dropDownListColor.SelectedIndex];
var LabelPrice = (Label)dataListItem.FindControl("LabelPrice");
LabelPrice.Text = color.Price;
}

When the DataList is data-bound, the AutoPostBack has not been handled yet, i.e. the values in the ItemCreated event are still the original values.
You need to handle the SelectedIndexChange event of the dropdown control.

Regarding your 2nd question:
I suggest you remove the AutoPostBack from the dropdown, add an "Update" button, and update the data in the button Click event.
The button can hold Command and CommandArgument values, so it's easy to associate with a database record.

some MSDN links with C# examples on bubbling
http://msdn.microsoft.com/en-us/library/system.web.ui.control.onbubbleevent.aspx
http://msdn.microsoft.com/en-us/library/aa719644(VS.71).aspx
http://msdn.microsoft.com/en-us/library/aa720044(VS.71).aspx

Thank You for your solution
protected void ddlOnSelectedIndexChanged(object sender, EventArgs e) {
try {
ModalPopupExtender1.Show();
if (ViewState["Colors"] != null) {
FillColors(ViewState["Colors"].ToString());
}
DropDownList dropDownListColor = (DropDownList)sender;
DataListItem dataListItem = (DataListItem)dropDownListColor.Parent;
Image image = (Image)dataListItem.FindControl("mdlImage");
Label ProductCode = (Label)dataListItem.FindControl("lblprdCode");
Label ProductName = (Label)dataListItem.FindControl("lblProdName");
DropDownList ddlQuantity = (DropDownList)dataListItem.FindControl("ddlQuantity");
Label ProductPrice = (Label)dataListItem.FindControl("lblProdPrice");
Label TotalPrice = (Label)dataListItem.FindControl("lblTotPrice");
//Label ProductPrice = (Label)dataListItem.FindControl("lblProdPrice");
} catch (Exception ex) {
}
}