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How to replace text in some cells of GridView after data binding?

I have a GridView that is assosiated with database. Here's a data binding:
protected void GridViewProgramms_SelectedIndexChanged(object sender, EventArgs e)
{
int rowIndex = ((GridView) sender).SelectedIndex;
var programid = ((GridView) sender).Rows[rowIndex].Cells[1].Text;
GridViewEx.RowEditing += GridViewEx_RowEditing;
SqlDataSource1.SelectParameters["ID"].DefaultValue = programid;
GridViewEx.DataBind();
ExcersicePanel.Visible = true;
PanelAp.Visible = false;
}
Everything works fine, but I need to change some cells values in GridView after that. I need to rewrite every Cell in the last row. How to do this without affecting the database?

You will need to write your code(To change the cell text) in RowDataBound event of the gridview after data bind
Refer following link for more explanation
Update GridView Column after databinding

protected void GridViewEx_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
label or textbox ddltype = (label or textbox)e.Row.FindControl("id");
ddltype.text="ur text";
}
}

How to change the color of label depending on certain values in the gridview

I have a sqldatasource and gridview.
I have two columns:
ID | Status
1 Closed
2 Opened
3 Waiting
How to change the color of the label in the view state of the gridview depeding on the value from the 'status' column.
For example if the value in the cell is "Closed" the label color will be red , if it's opened then it will become green and so on.
I've thought about looping through all cells of the status column and if the cell contains a certain value the color will change. ( in row data bound event ) . But I haven't done this because I don't find this idea as a good one because of the looping part.

use the RowDataBound event from the grid view to check what is the status. You don't need to do a loop because that event (if you register or not) is being called.
One thing to note, you will need to make sure you are looking at the right row (header, footer, alternate etc) so something like this
void YourGridViewName_RowDataBound(Object sender, GridViewRowEventArgs e)
{
if(e.Row.RowType == DataControlRowType.DataRow)
{
// Do your color change here by accessing the col with e.Row.Cells[column_index].BackColor = 'what ever you want'
}
}

You can enable the RowDataBound Event in the markup
<asp:GridView ID="gridview1" runat="server" OnRowDataBound="RowDataBound">
</asp:GridView>
And put this in your Code-Behind file.
protected void RowDataBound(Object sender, GridViewRowEventArgs e)
{
if(e.Row.RowType == DataControlRowType.DataRow)
{
// Retrieve the underlying data item. In this example
// the underlying data item is a DataRowView object.
DataRowView rowView = (DataRowView)e.Row.DataItem;
// Retrieve the state value for the current row.
String state = rowView["state"].ToString();
//format color of the as below
if(state == "Closed")
(e.Row.FindControl("lbl1") as Label).BackColor = Color.Red;
if(state == "Open")
(e.Row.FindControl("lbl1") as Label).BackColor = Color.Green;
if(state == "Waiting")
(e.Row.FindControl("lbl1") as Label).BackColor = Color.Yellow;
}
}

You have to write code in the rowdatabound event of your grid view.
Example:
private GridView1_RowDatabound(object sender,EventArgs e)
{
if(e.Row.RowType == DataControlRowType.DataRow)
{
// You have to put your logic here.
if( e.Row.Cells[1].Text == "closed" )
{
// to get a reference to label control
Label lb = e.Row.FindControl("LabelCOntrolID");
}
}
}

How to highlight specific row in a DetailsView?

I am a new ASP.NET developer. I am using a DetailsView now to dispaly some data from the database. I have the need to highlight certain two rows from the DetailsView. Both rows are VARCHAR data type.
SO HOW TO DO THAT?

Override the databound event and set the e.Row.BackColor = System.Drawing.Color.Red; or what ever color, if you have some logic to execute for finding the row that needs to be highlighted.
protected void detailsView_RowDataBound(object sender,
GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
if(...)//some condition for selection of row to be higlighted
{
e.Row.BackColor = System.Drawing.Color.Red;
}
}
}
If you need a perticular row, say 4th row to be highlighted and that's fixed then you could directly like this
detailsViewGrid.Rows[3].Row.BackColor = System.Drawing.Color.Red;
The only thing you need to keep in mind that this code would be written in only those events which would come after grid_rowdatabound event(Like pre-render)

Gridview sorting when Header text changed in RowDataBound event

I have a GridView on my webpage whose DataSource is a DataTable which is populated at runtime. AllowSorting property of GridView is True. I have successfully implemented manual sorting for this GridView.
But I had to translate the webpage to other languages for which I used local resource files. I changed the Header text of GridView columns in RowDataBound event. Since then I'm unable to sort the GridView.
protected void GVSummaryTable_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.Cells.Count > 0)
{
//Translate header text
if (e.Row.RowType == DataControlRowType.Header)
{
e.Row.Cells[0].Text = GetLocalResourceObject("GVSummaryTableName").ToString();
e.Row.Cells[1].Text = GetLocalResourceObject("GVSummaryTableLoginLevel").ToString();
e.Row.Cells[2].Text = GetLocalResourceObject("GVSummaryTableLoginID").ToString();
e.Row.Cells[4].Text = GetLocalResourceObject("GVSummaryTableDate").ToString();
}
}
}
What should I do to enable sorting for the columns?
Any help would be appreciated. Thanks!

Changing the code to below solved the problem:
if (e.Row.RowType == DataControlRowType.Header)
{
LinkButton LnkHeaderText = e.Row.Cells[1].Controls[0] as LinkButton;
LnkHeaderText.Text = "Name";
}

I am not sure if the problem is related to the Header text since the sorting is normally done with the Sort Expression. Please, make sure you are also giving a value to this property when doing the Sorting. Hope this helps!

gridview, how to build a image url in code behind?

I have a gridview control which contains an image field. However, the image url is built from several fields in my returned dataset. How do you concatenate those fields together, and at which point do I do this so that I can pass that image url do my imagefield in my gridview? I am guessing it's on the RowDataBound but I don't know how to access each of the rows in my dataset?
Thanks.

I'm not sure what you are trying to concatenate without a code example, however I would perform the concatenation before binding the gridview and store it in a private member on the class so that you can access it later in the RowDataBound event.
You can use the row data bound event to find the control within that row and set its ImageUrl property.
private string m_ConcatUrl;
protected void gridView_RowDataBound(Object sender, GridViewRowEventArgs args)
{
if(args.Row.RowType == DataControlRowType.DataRow)
{
Image imgCtrl = (Image) args.Row.FindControl("imgCtrl");
imgCtrl.ImageUrl = m_ConcatUrl;
}
}

You can use RowDataBound event to set the cell value.
void YourGridView_RowDataBound(Object sender, GridViewRowEventArgs e)
{
if(e.Row.RowType == DataControlRowType.DataRow)
{
// You can set your cell value in this
e.Row.Cells[index] // use this to set the value in the cell
}
}

In .NET 4, it would be like this:
if (e.Row.RowType == DataControlRowType.DataRow)
{
string1 = e.Row.Cells[i].Text;
}
i is the index of the particular column you want to reference (e.g. Cells[0] is column 1).
I'm not sure if it's different in 3.5 but try that.