C# Add HyperLinkColumn to GridView - c#

I'm trying to add HyperLinkColumns dynamically to my GridView. I have the following code:
HyperLinkColumn objHC = new HyperLinkColumn();
objHC.DataNavigateUrlField = "title";
objHC.DataTextField = "Link text";
objHC.DataNavigateUrlFormatString = "id, title";
objHC.DataTextFormatString = "{2}";
GridView1.Columns.Add(objHC);
This doesn't work, so.. how can i add a HyperLinkColumn to my GridView?

You might want to add it when the row is binded:
protected void yourGrid_RowDataBound(object sender, GridViewRowEventArgs e)
{
HyperLink hlControl = new HyperLink();
hlControl.Text = e.Row.Cells[2].Text; //Take back the text (let say you want it in cell of index 2)
hlControl.NavigateUrl = "http://www.stackoverflow.com";
e.Row.Cells[2].Controls.Add(hlControl);//index 2 for the example
}

You have to do it before the DataBinding takes place, check the GridView Events.

I think you should be using a HyperLinkField not a HyperLinkColumn.

In case, if you just want to redirect to another URL then simple use HyperLink web control and push it in the desired cell of GridView Row at RowDataBound event.
OR
If you want to perform any server event before sending it to another URL, try this
1) Add LinkButton object at RowDataBound event of GridView.
2) Set the CommandName, CommandArgument property, if requried to pass any data to this object.
3) Capture this event by handling the RowCommand event of the GridView.

By the way, I just think that you can use the DataGridView and in the Designer select the Link column and your problem would be over. The DataGridView does have a link column, than you just need to add an event on "Click" and you will be able to have what you want. This solution works if you can switch to DataGridView.

I know this thread is old but couldn't help adding my 2 cents. The procedure explained in the following tutorial worked perfectly for me:
ASP Alliance

It seems you have got things mixed up. I don't know - how that code compiles?
GridView's column collection can accept columns of type "DataControlField".
I think you need to initialize HyperLinkField and set relevant properties (text, NavigateUrl, HeaderText, Target) and add it to the columns collection.
HyperLinkColumn class is meaningful when you are using DataGrid (not in case of GridView).
Hope that helps.

Related

AspxGridView initially load empty

I asked this question here, too: http://www.devexpress.com/Support/Center/p/Q388764.aspx
but I hope for a quicker answer here.
I need my grid to display data only after the user starts filtering.
This is the scenario:
When opening a page containing the grid, the grid should no even try to display the data.
When the user starts searching (applies a filter), the data should be displayed.
Is this possible?
Thanks.
Ref: this
Subscribing to DataBinding event resolved all troubles with correct behavior actions like sorting, filtering and groupping events of ASPxGridView in runtime mode with requirement of getting DataTable for ASPxGridView.DataSource.
And you have answered at devexpress also it was also using the idea to implement this as i have looked by above reference link:
protected void gvData_DataBinding(object sender, EventArgs e) {
if (Convert.ToBoolean(Session["need_bind"]))
gvData.DataSource = DSource;
else
gvData.DataSource = null;
}
along this use ASPxGridView.ProcessColumnAutoFilter event handler
Do not bind the data in the Page_load.
Bind the grid to the datasource in the filter event/ search button click event..
Make the grid default to a filter that returns no records. The end user can then filter\search themselves and the ajax callbacks will repopulate the grid.

Gridview making a column invisable

Hi I have a grid view which is dynamically generated via C# using a DataSet.
I'm passing a row ID field (from the database) to the grid view, as this is required when a user clicks to edit a records. However I don't want the user to be able to view the column.
I have tried the following but it doesn’t seem to work? Could anyone suggest a way to hide the column or a better way of attaching the information to the grid view row so it can be used at a later stage.
c#
DataColumn ColImplantCustomerDetailsID = new DataColumn();
ColImplantCustomerDetailsID.ColumnName = "Implant ID";
ColImplantCustomerDetailsID.DataType = typeof(int);
ColImplantCustomerDetailsID.Visable = false; <-- visable doens't work here.
asp.net
DataColumn doesn't have a 'Visable' property. Heck, it doesn't have a 'Visible' property either.
Use this before you bind
gridviewNameHere.Columns[index].Visible = false;
You can make it visible again on one of your event handlers.
Another option, rather than hiding the column, is to use the DataKeyNames property of the GridView to store the name of the ID field. You can then use myGridView.SelectedValue to retrieve the selected ID.
Use the index of the column to hide it when you initialize it...
grid.Columns[index].Visible = false;
I actually hide a few things as you are suggesting, example - database status names for that row that can be used in code that the user does not need to see.
Accessing GridView Invisible Columns
http://www.highoncoding.com/Articles/178_Access_GridView_Invisible_Columns.aspx
In the OnRowDataBound event of the GridView component:
// c#
protected void gv_RowDataBound(object sender, GridViewRowEventArgs e)
{
int index = 0; // put the index of the column you need hide.
e.Row.Cells[index].Visible = false;
}

how to clear gridview

I want to clear my gridview. I have 2 GridViews and Has Select Button On It. on Selecting this button that item goes into the second gridview. now the question is how should i clear the second grid view. I am trying the clear method but clear method is not found in my visual studio..
dataGridView1.DataSource = null;
or
dataGridView1.Rows.Clear();
gridview.DataSource = null;
//rebind to gridview
gridview.DataBind();
Bind the Gridview to an empty list.
Binding it to 'null' like Patrick Kafka mentioned should work - unless you have some column requirements (I'm mentioning it because I have a tendancy to plug in javascript into my gridviews and unless you specify those columns in the markup, they won't be generated and it will cause errors in the js. (This is also relevant to those getting errors after doing Columns.Clear )
In a case like that (as well as in all other cases), you can simply bind the gridview to a new instance (or empty instance) of your datasource. (Below example for a gridview bound to a datatable - it could be bound to new List<T>() as well).
grdiview1.DataSource = new DataTable();
grdiview1.DataBind();
dataGridView1.Columns.Clear(); //this clears the entire Gridview
Simply add the following c# code to clear the GridView:-
gridView.Rows.Clear();

asp.net finding column from dynamic gridview

I'm creating a dynamic GridView from a DataTable that is returned from a stored procedure. I call and bind with the following code:
DataTable dt = Sql.reportData(Convert.ToInt32(Session["userID"]));
this.GridView1.DataSource = dt.DefaultView;
this.GridView1.DataBind();
I need to restyle certain columns but they are not always the same column number, and only have the headers text string to identify it. Is there an easy way to track a column down like this so I can edit its attributes?
Thanks,
Alex
I've run into this myself. You've got to loop through the column names, get the index, and then refer to the index to manipulate the style.
Muhammad is right about the timing, but you won't be searching for a label--it seems you want to style the entire column, right?
http://forums.asp.net/p/1076872/1584635.aspx
the above has several versions of a solution.
The best place to find the control and use it will be in the RowCreated event. RowDataBound should not be used because you dont have to manipulate the data with which the column is being binded. So restyle the elements in the column by searching them in the RowCreated event.
protected void GridView1_RowCreated(object sender, GridViewRowEventArgs e)
{
e.Row.FindControl("");
}

Set boundcolumn width in gridview isn't working

I have a report page that can display two different reports. So I have a GridView with no columns on my aspx page. I am adding 4 BoundFields to the GridView in the button click event handler. The first column is the one I need to set the width of for one of the reports (the code I'm using to add this column is below).
gvReport.Columns.Clear();
BoundField bf1 = new BoundField();
...
if (ddReportType.SelectedValue == "full") {
bf1.HeaderText = "Facility";
bf1.DataField = "Facility";
bf1.ItemStyle.Wrap = true;
bf1.ItemStyle.Width = 150;
bf1.Visible = true;
gvReport.Columns.Add(bf1);
...
The problem is there is one row that has a SHA512 hash in this column. Since there is no space in the middle of it, the gridview won't wrap it (I think that's what is happening, anyway)! So I thought I'd catch this column in the OnRowDataBound event and add a space in the middle of the hash so it will wrap, but I can't figure out how to reference the BoundField. There's no ID property. Does anyone have a suggestion? Either on how to reference the BoundField, or another way to get this to display nicely?
I had the columns in the aspx file originally and tried using:
gvReport.Columns[0].ItemStyle.Width = 150;
gvReport.Columns[0].ItemStyle.Wrap = true;
but that didn't work either. This is very frustrating!
So we went with Plan C. I never did figure out how to reference the BoundField. We got around that problem by creating two GridViews in the markup and just changing which one is visible. To solve the problem of the text that won't wrap, we're catching it in the OnRowDataBound event handler and checking the length of the text. We just insert a space in the middle, and voila! It wraps!
The BoundField is a wrong thing. It is more like a definition. Later, when binding or creating rows, you are dealing with rows, cells, and data items.
You could do something like this:
protected void grid_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
string value = e.Row.Cells[1].Text;
if (!string.IsNullOrEmpty(value))
e.Row.Cells[1].Text = value.Insert(value.Length / 2, " ");
}
}
where Cell[1] is the column containing long values. In the same place, you could use e.Row.DataItem to get actual data, but then you'd need to know its type.
You could create a template field and bind to an expression or use its child's data bound event to do the same.
Also, if you were using a DataSet, you could set up calculated field and bind to it. Anyway...

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