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Remove Row from GridView

I have a grid view on my page and I want to allow the user to add / remove items to it. How it works, and the add functionality does work albeit probably not great, is that a user selects a product from a drop down list, then clicks Add.
This creates a new row in grid with the select Product text and ID. The GridView markup is:
<asp:GridView runat="server" ID="grdSelectedProducts" BorderWidth="1px" CellPadding="3" CellSpacing="2" AutoGenerateColumns="False" OnRowDataBound="grdSelectedProducts_OnRowDataBound" ShowHeaderWhenEmpty="True" DataKeyNames="ProductId"
OnRowCommand="grdSelectedProducts_RowCommand" OnRowDeleted="grdSelectedProducts_RowDeleted" OnRowDeleting="grdSelectedProducts_RowDeleting">
<Columns>
<asp:BoundField DataField="Product" HeaderText="Product" ReadOnly="False" />
<asp:TemplateField>
<ItemTemplate>
<asp:LinkButton runat="server" ID="linkDelete" runat="server" CommandName="Delete" CommandArgument="<%# Container.DataItemIndex %>">Remove</asp:LinkButton>
</ItemTemplate>
</asp:TemplateField>
<asp:BoundField DataField="ProductId" HeaderText="ProductId" ReadOnly="False" Visible="False" />
</Columns>
</asp:GridView>
The data in the grid is bound but there is no connection to a database, as it's just the information from the drop down.
The linkDelete is where I want to allow the user to remove an item, so my question is, how can I actually delete the row? I've got the RowCommand event up which I've tried to remove it, but it just doesn't seem to work correctly as the table either 1) gets rebound with the same data as before or 2) all rows are removed due to the binding of a new DataTable. I'm missing something obvious, but this type of grid is new to me.
Any example I've seen here or on Google has been around gridviews which are databound from SQL, or some other database, which seems to make the rebinding easier. However my version doesn't use that so binding again doesn't seem to work correctly.
protected void grdSelectedProducts_RowCommand(object sender, GridViewCommandEventArgs e)
{
if (e.CommandName == "Delete")
{
if (!string.IsNullOrEmpty(e.CommandArgument.ToString()))
{
int rowIndex = Convert.ToInt32(e.CommandArgument);
grdSelectedProducts.DeleteRow(rowIndex);
CountryDataTable = (DataTable)grdSelectedProducts.DataSource;
DataTable table = CreateDataTable(false, string.Empty, string.Empty);
grdSelectedProducts.DataSource = table;
grdSelectedProducts.DataBind();
}
}
}
private DataTable CreateDataTable(bool isAddingValue, string selectedProduct, string selectedId)
{
// if isAddingValue is FALSE then it isn't from a button click to add a Product, it is just
// a call to create the datatable
DataTable dataTable = ProductDataTable;
if (!dataTable.Columns.Contains("Product"))
{
dataTable.Columns.Add("Product");
dataTable.Columns.Add("ProductId");
}
if (isAddingValue)
{
// Get the data from ViewState
DataRow dataRow;
dataRow = dataTable.NewRow();
dataRow["Product"] = selectedProduct;
dataRow["ProductId"] = selectedId;
dataTable.Rows.Add(dataRow);
}
else
{
grdSelectedProducts.DataSource = null;
grdSelectedProducts.DataSource = ProductDataTable;
grdSelectedProducts.DataBind();
}
// Save the data back to ViewState
ProductDataTable = dataTable;
return dataTable;
}
private DataTable ProductDataTable
{
get {return ViewState["ProductDataTable"] as DataTable ?? new DataTable(); }
set { ViewState["ProductDataTable"] = value; }
}
I do have the RowDeleting & RowDeleted events but I don't have any code in it.

First thing you should note is you are deleting the row from grid not from the data table
Then you again bind the data table which may not give you any change, What you should do is instead of deleting from grid delete it from datatable
Rewrite it like
if (e.CommandName == "Delete")
{
if (!string.IsNullOrEmpty(e.CommandArgument.ToString()))
{
int rowIndex = Convert.ToInt32(e.CommandArgument);
DataTable table = CreateDataTable(false, string.Empty, string.Empty);
table.Rows.RemoveAt(rowIndex)
grdSelectedProducts.DataSource = table;
grdSelectedProducts.DataBind();
}
}
If you need it to remove it from DB , DOnt forget to do that , And also note that the above code each time when u fetch the table it will give u everything from DB
so you can make it global , or you can just remove from DB

try this code
if (e.CommandName == "Delete")
{
if (!string.IsNullOrEmpty(e.CommandArgument.ToString()))
{
int rowIndex = Convert.ToInt32(e.CommandArgument);
grdSelectedProducts.DeleteRow(rowIndex);
SqlCommand cmd = new SqlCommand ("Delete from table where id='"+ rowIndex )+"'",ConnectionObject);
cmd.ExecutenonQuery();
CountryDataTable = (DataTable)grdSelectedProducts.DataSource;
DataTable table = CreateDataTable(false, string.Empty, string.Empty);
grdSelectedProducts.DataSource = table;
grdSelectedProducts.DataBind();
}
}

Trouble grabbing Row Number from GridView

I have the following GridView:
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" DataKeyNames="SysInvoiceID" DataSourceID="SqlDataSource1">
<Columns>
<asp:BoundField DataField="SysInvoiceID" HeaderText="SysInvoiceID" ReadOnly="True" SortExpression="SysInvoiceID" />
<asp:BoundField DataField="BillMonth" HeaderText="BillMonth" SortExpression="BillMonth" />
<asp:BoundField DataField="InvoiceDate" HeaderText="InvoiceDate" ReadOnly="True" SortExpression="InvoiceDate" />
<asp:BoundField DataField="InvoiceNumber" HeaderText="InvoiceNumber" SortExpression="InvoiceNumber" />
<asp:BoundField DataField="Net" HeaderText="Net" SortExpression="Net" />
<asp:BoundField DataField="VAT" HeaderText="VAT" SortExpression="VAT" />
<asp:BoundField DataField="Gross" HeaderText="Gross" SortExpression="Gross" />
<asp:ButtonField CommandName="ViewInvoice" HeaderText=" " ShowHeader="True" Text="View" />
</Columns>
</asp:GridView>
Here is the code behind the page:
public partial class PagingTest01 : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
void GridView1_RowCommand(Object sender, GridViewCommandEventArgs e)
{
// If multiple buttons are used in a GridView control, use the
// CommandName property to determine which button was clicked.
if (e.CommandName == "ViewInvoice")
{
// Convert the row index stored in the CommandArgument
// property to an Integer.
int index = Convert.ToInt32(e.CommandArgument);
// Retrieve the row that contains the button clicked
// by the user from the Rows collection.
GridViewRow row = GridView1.Rows[index];
// Now you have access to the gridviewrow.
ViewButton_Click(row);
}
}
protected void ViewButton_Click(GridViewRow row)
{
byte[] FileImage = GetImageData(0,row);
if (FileImage != null)
{
base.Response.Clear();
base.Response.Buffer = true;
base.Response.ContentType = "Application/x-pdf";
base.Response.ContentEncoding = Encoding.Default;
string attachment = string.Format("attachment;filename=\"Invoice_{0}.pdf\"", "Customer1");
base.Response.AddHeader("content-disposition", attachment);
base.Response.BinaryWrite(FileImage);
base.Response.Flush();
base.Response.Close();
base.Response.End();
}
}
public byte[] GetImageData(int sysInvoiceID, GridViewRow row)
{
string strUserID = CommonCode.GetCurrentUserID().ToString();
string strCustomerID = CommonCode.GetCurrentCustomerID().ToString();
byte[] numArray;
string strConnectionString = "Data Source=TESTSERV;Initial Catalog=DB_Invoices;Persist Security Info=True";
SqlConnection connection = new SqlConnection(strConnectionString);
SqlCommand command = new SqlCommand("select FileImage from DB_Invoices.dbo.Bills WHERE (FileType = 'PDF' AND SysInvoiceID = #ID)", connection);
command.Parameters.AddWithValue("#ID", GridView1.Rows[row].Cells[0].Text);
SqlDataAdapter da = new SqlDataAdapter(command);
DataSet ds = new DataSet();
try
{
connection.Open();
da.Fill(ds);
DataRow item = ds.Tables[0].Rows[0];
byte[] item1 = (byte[])item["FileImage"];
ds.Tables.Clear();
numArray = item1;
}
catch (Exception ex)
{
throw ex;
}
finally
{
connection.Close();
}
return numArray;
}
}
So basically I have a GridView with a lot of rows, each one with a 'View' Buttonfield next to it. When 'View' is clicked, I attempted to make use of GridView1_RowCommand which should hopefully grab the row clicked before passing it onto ViewButton_Click. This will then call GetImageData and pass the row number onto this line:
command.Parameters.AddWithValue("#ID", GridView1.Rows[row].Cells[0].Text);
Cell 0 is the SysInvoiceID column, so if the correct row is passed, #ID will be assigned a SysInvoiceID.
'Row' however doesn't seem to be a valid argument, though I can't think why not... Unless I have to explicitly convert it into a int? Any help would be really appreciated! Thanks.

I have just commented this as side-note but maybe it's your issue because you mention that "it doesn't seem to be a valid argument, though I can't think why not... Unless I have to explicitly convert it into a int".
If ID is an int you should use int.Parse(celltext), othwerwise the database gets the wrong type since AddWithValue needs to infer the type from the value.
So use:
command.Parameters.AddWithValue("#ID", int.Parse(GridView1.Rows[row].Cells[0].Text));
Apart from that, you haven't added the event handler GridView1_RowCommand.
<asp:GridView ID="GridView1" OnRowCommand="GridView1_RowCommand" runat="server" AutoGenerateColumns="False" DataKeyNames="SysInvoiceID" DataSourceID="SqlDataSource1">
....
and you are also not setting the CommandArgument to the index of the row. I would use a different approach anyway if you need the row-index. Use a templatefield and a control, for example a Button. Then use it's NamingContainer property to get the reference to the 'GridViewRow`, here is an example: Get Row Index on Asp.net Rowcommand event

use this:
int index = ((GridViewRow)((WebControl)sender)).RowIndex;
in place of
int index = Convert.ToInt32(e.CommandArgument);

Changing the color of a row in gridview according to the data

I have a Gridview in ASP.Net - C#. I have one column that is named Assignment or Exam. In that column, I have the name of either the assignment or exam, ex.: "Exam 1", "Assignment 5" I want that each row that is an assignment should be red and exam be blue.
What is the best way to do it, in SQL Server, or in my code? if so what is the proper code?

You set the background colour of a row in a Gridview by setting the BackColor property for each row individually. To do this based on the data in the row, you'll need to examine the row as it's being bound, which you can do inside the RowDataBound event. Here's a quick bit of markup for a basic Gridview where we hook up to the server-side event:
<asp:GridView runat="server" AutoGenerateColumns="False" OnRowDataBound="TestGridView_RowDataBound" ID="TestGridView">
<Columns>
<asp:BoundField DataField="Type" HeaderText="Assignment/Exam" />
<asp:BoundField DataField="Name" HeaderText="Name" />
</Columns>
</asp:GridView>
protected void Page_Load(object sender, EventArgs e)
{
DataTable tests = new DataTable();
tests.Columns.Add(new DataColumn("Type"));
tests.Columns.Add(new DataColumn("Name"));
tests.AcceptChanges();
tests.Rows.Add(new []{"Assignment","StackOverflow Basics"});
tests.Rows.Add(new[]{"Exam","Expert Markdown"});
tests.Rows.Add(new[]{"Exam","Upvoting"});
tests.Rows.Add(new[]{"Assignment","Rep Changes"});
TestGridView.DataSource = tests;
TestGridView.DataBind();
}
In the code for the event, we can get hold of the individual data row that we're binding to and examine the value, so we can set the BackColor accordingly:
protected void TestGridView_RowDataBound(object sender, GridViewRowEventArgs e)
{
// Ignore the first row which is the header
if (e.Row.RowType == DataControlRowType.DataRow)
{
// Get hold of the row and then the DataRow that it's being bound to
GridViewRow row = e.Row;
DataRow data = ((DataRowView)row.DataItem).Row;
// Look at the value and set the colour accordingly
switch (data.Field<string>("Type"))
{
case "Assignment":
row.BackColor = System.Drawing.Color.FromName("Blue");
break;
case "Exam":
row.BackColor = System.Drawing.Color.FromName("Red");
break;
}
}
}
That works fine, although you might want to also consider setting the text colour to white so it's slightly easier to read.
However, you might want some more flexibility in the future e.g. if you add a third assessment type called 'Lab' coloured green, you'd need to change/recompile/retest/redeploy the code. If instead, you pass a named colour up from the database and then use that in the RowDataBound event, you can avoid some of that work, e.g.:
protected void TestGridView_RowDataBound(object sender, GridViewRowEventArgs e)
{
// Ignore the first row which is the header
if (e.Row.RowType == DataControlRowType.DataRow)
{
// Get hold of the row and then the DataRow that it's being bound to
GridViewRow row = e.Row;
DataRow data = ((DataRowView)row.DataItem).Row;
row.BackColor = System.Drawing.Color.FromName(data.Field<string>("BackColour");
row.ForeColor = System.Drawing.Color.FromName(data.Field<string>("TextColour");
}
}

First find the row index in a variable. In the following code I have used index as the variable.
grdWithLocation.Rows[index].BackColor = Color.FromArgb(255, 238, 238, 238);

I use this in my inventory database. it check to see what date it is and compares it to the dates in the database for each order. it then colours each row with a different colour depending on how long they have been sitting. it is on the RowDataBound of the GridView
You should be able to modify the code to chanage the dates to Exam/Assignment
if (e.Row.RowType == DataControlRowType.DataRow)
{
DateTime datToday = DateTime.Today();
DateTime O1 = datToday.AddDays(0);
DateTime O2 = datToday.AddDays(-1);
DateTime O3 = datToday.AddDays(-4);
string strMediaX = e.Row.Cells[2].Text;
if (Information.IsDate(strMediaX))
{
DateTime MediaX = e.Row.Cells[2].Text;
if (MediaX < O3)
{
e.Row.Cells[2].BackColor = Drawing.Color.OrangeRed;
e.Row.Cells[2].ForeColor = Drawing.Color.White;
}
else if (MediaX < O2)
{
e.Row.Cells[2].BackColor = Drawing.Color.Orange;
e.Row.Cells[2].ForeColor = Drawing.Color.White;
}
else if (MediaX < O1)
e.Row.Cells[2].BackColor = Drawing.Color.Gold;
}
// checks the current stock of the item and if it is below 10 then it changes the colour to highlight that it needs to be ordered.
if (e.Row.RowType == DataControlRowType.DataRow)
{
if ((Label)e.Row.Cells[9].FindControl("lblCurrentStock").Text < 11)
{
e.Row.Cells[9].BackColor = System.Drawing.Color.OrangeRed;
e.Row.Cells[9].ForeColor = Drawing.Color.White;
e.Row.Cells[9].Font.Bold = true;
}
}
}

Question about checkbox and datagridview

I have datagridview with checkbox column, and the checkbox within the column can be checked or unchecked with external checkbox. It works fine while selecting all the columns and saving the data in database. But, when I unchecked the checkbox in the datagridview with external checkbox and again select the single checkbox within the datagridview, it again takes the rowindex of all the checkbox within the column.
if (chkbranches.Checked == true)
{
foreach (DataGridViewRow dr in gridviewholiday.Rows)
{
dr.Cells[0].Value = true;
}
for (int i = 0; i < gridviewholiday.Rows.Count; i++)
{
rowindex = i;
list.add(rowindex);//to put the rowindex in array list
}
}
else if (chkbranches.Checked == false)
{
foreach (DataGridViewRow dr in gridviewholiday.Rows)
{
dr.Cells[0].Value = false;
gridviewholiday.Refresh();
gridviewholiday.ClearSelection();
list.Clear();
}
}

Why do you loop twice if chkbranches is checked? Can't you add items to the list within the first foreach? And in the loop for unchecking, why do you refresh, and clear both controls each time? Probably only needed once.
And as mentioned, this isn't doing anything about single checks. If you're expecting it to, that seems to be the problem.

Not quite sure what your attempting to do, but I have something similar with a button that deletes all the checked rows. I use a template field like so for the check box:
<asp:TemplateField>
<ItemTemplate>
<asp:CheckBox ID="cbSelector" runat="server" />
</ItemTemplate>
</asp:TemplateField>
Then for the Delete button code behind I do:
protected void btnDeleteChecked_Click(object sender, EventArgs e)
{
foreach (GridViewRow row in gridOrders.Rows)
{
CheckBox cb = (CheckBox)row.FindControl("cbSelector");
if ((null != cb) && cb.Checked)
{
uint id = Convert.ToUInt32(gridOrders.DataKeys[row.RowIndex].Value);
gInvoiceDB.DeleteInvoice(id, true);
}
}
}

How can I access DataGridRow from a textbox on that row?

In a DataGrid, when text in a textbox changes I want to add the value of another field in that row to an array.
public void txtTitle_TextChanged(object sender, EventArgs e)
{
TextBox titleBox = (TextBox)sender;
DataGridItem myItem = (DataGridItem)titleBox.Parent.Parent;
string test = DataBinder.Eval(myItem.DataItem, "prod_id").ToString();
}
However myItem.DataItem evaluates as null. I was expecting it to evaluate as DataRowView?

You can get the TextChanged event to fire if you do the following:
<asp:DataGrid ID="DataGrid1" runat="server" AutoGenerateColumns="False"
onitemdatabound="DataGrid1_ItemDataBound">
<Columns>
<asp:TemplateColumn HeaderText="Test">
<ItemTemplate>
<asp:TextBox OnTextChanged="txtBox_TextChanged" ID="TextBox1" runat="server" AutoPostBack="True"></asp:TextBox>
</ItemTemplate>
</asp:TemplateColumn>
<asp:BoundColumn DataField="Name" HeaderText="Test 1"></asp:BoundColumn>
</Columns>
</asp:DataGrid>
You will notice that i have the following properties set:
AutoPostBack="True"
I have also manually added the OnTextChanged="txtBox_TextChanged" to the text box as well.
In my code behind i have:
protected void txtBox_TextChanged(object sender, EventArgs e)
{
TextBox txtBox = (TextBox)sender;
Label1.Text = txtBox.Text;
}
The only way the event will fire is when you lose focus on the text box after typing.
Key points to consider:
This will cause a post back, so Ajax might be a good way to keep the user experience nice.
You will need to make sure you wrap your DataBind() in a if (!IsPostBack)
Hope this helps!

Effectively, I solved this by adding an autonumber column to the table, and using the value of this to determine the row's positino in the table, then using the value of this to affect the appropriate row in the datagrid.
I'm now merely changing the color of the row rather than adding values in that row to an array, as stated in the original question.
public void txtPrice_TextChanged(object sender, EventArgs e)
{
TextBox txtPrice = (TextBox)sender;
DataGridItem myItem = (DataGridItem)txtPrice.Parent.Parent;
markRows(myItem, true);
}
public void markRows(DataGridItem myItem, bool toSave)
{
// Prepeare to save this record?
CheckBox thisSave = (CheckBox)myItem.FindControl("chkSave");
thisSave.Checked = toSave;
// Establish the row's position in the table
Label sNo = (Label)myItem.FindControl("SNo");
int rowNum = Convert.ToInt32(sNo.Text) - 1;
CheckBox rowSave = (CheckBox)grid.Items[rowNum].FindControl("chkSave");
// Update background color on the row to remove/add highlight
if (rowSave.Checked == true)
grid.Items[rowNum].BackColor = System.Drawing.Color.GreenYellow;
else
{
Color bgBlue = Color.FromArgb(212, 231, 247);
grid.Items[rowNum].BackColor = bgBlue;
// some code here to refresh data from table?
}
}