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Getting name of table columns in gridview in addition to custom names

I have a simple grid on my ASPX page and I am binding it with data coming from a select query on button click event. I am not sure how to bind columns of this table with my grid as currently I am getting 8 columns, 4 with the header given in aspx page and 4 with headers of table columns. Below is my button click event code.
protected void btnSearch_Click(object sender, EventArgs e)
{
MyBookListCont myBookListCont = new MyBookListCont();
gdvMyBooks.DataSource = myBookListCont.SearchBookDetailsCont();
gdvMyBooks.DataBind();
}
And below is aspx code of gridview.
<asp:GridView ID="gdvMyBooks" runat="server">
<Columns>
<asp:BoundField DataField="BK_NM" HeaderText="Book Name" />
<asp:BoundField DataField="ATHR_NM" HeaderText="Author Name" />
<asp:BoundField DataField="BUY_YR" HeaderText="Buy Year" />
<asp:BoundField DataField="PRICE" HeaderText="Price" />
</Columns>
</asp:GridView>
Looks like a silly question, but help would be much appreciated.

This is because you have explicitly specified 4 columns in this design code :
<Columns>
<asp:BoundField DataField="BK_NM" HeaderText="Book Name" />
<asp:BoundField DataField="ATHR_NM" HeaderText="Author Name" />
<asp:BoundField DataField="BUY_YR" HeaderText="Buy Year" />
<asp:BoundField DataField="PRICE" HeaderText="Price" />
</Columns>
Now here, as you can see, there is a HeaderText property which will override the table column name and display the text that is mentioned in here.
You have a couple of options here that you can try :
First, if you want all columns like this with custom header text, you can define all the other columns with these 4 in the same manner as well. That will display all the data and column headers as per the given format.Something like this :
<asp:GridView ID="gdvMyBooks" AutoGenerateColumns="False" runat="server">
<Columns>
<asp:BoundField DataField="BK_NM" HeaderText="Book Name" />
<asp:BoundField DataField="ATHR_NM" HeaderText="Author Name" />
<asp:BoundField DataField="BUY_YR" HeaderText="Buy Year" />
<asp:BoundField DataField="PRICE" HeaderText="Price" />
//other columns using same syntax as above.
</Columns>
</asp:GridView>
Also, if you dont want to bind all columns coming in your query, you can use this attibute in your gridview,
AutoGenerateColumns = False
And just specify the columns that you need like you have currently done.
The other thing is, if you want to straight away bind the result in your query to your GridView, then just remove those 4 BoundField statements and leave as it is. This will bind your table to GridView with the same header names as the column names.
I hope this makes things clear.

You have to set your GridView.AutoGenerateColumns to false :
<asp:GridView ID="gdvMyBooks" runat="server" AutoGenerateColumns="False">
Otherwise, it will bind all the field of your object.

Is it possible to change gridviewid to to a gridview DataSouce after the gridview is loaded

Is it possible to change a gridviews DataSouceId to a gridview DataSouce after the gridview is loaded. I have a gridview with a DataSouceId that is equal to SqlDatasource. I have a button when pressed executes a some LINQ which I want to change what's in the gridview.
var sce = from pk in db.Tables
where pk.Score > 20
select new { pk.First_Name, pk.Last_Name, pk.Score };
GridView1.DataSourceID = "";
GridView1.DataSource = sce;
GridView1.DataBind();
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" DataKeyNames="First Name" DataSourceID="SqlDataSource2" AllowSorting="True">
<Columns>
<asp:BoundField DataField="First Name" HeaderText="First Name" ReadOnly="True" SortExpression="First Name" />
<asp:BoundField DataField="Last Name" HeaderText="Last Name" SortExpression="Last Name" />
<asp:BoundField DataField="Score" HeaderText="Score" SortExpression="Score" />
<asp:BoundField DataField="Nationality" HeaderText="Nationality" SortExpression="Nationality" />
</Columns>
</asp:GridView>
I tried to change to a empty string. This compiles but crashes when the button is clicked.
Is what I'm trying possible?

The problem is that the query defines columns with different names from what the GridView expects. For example, compare:
pk.First_Name
and
DataField="First Name"
These are different, theerefore GridView is not able to find the column in data source and throws exception.
The best option would be to use underscore in GridView as well. That might require some refactoring in your initial SQL, but it should e done anyway - having spaces in column names is very brittle and uncommon, better refrain from it altogether:
<asp:BoundField DataField="First_Name" ...
Or you can define a TemplateField that looks for column with either name and displays what was found. But that sounds like a terribly huge overhead.

image as header for each column in grid view

I have a data table which is displayed as a gridview in ASP.NET. It has a column: temperature . I want to put picture of thermometer instead of writing temperature. I want this picture only for this column and not for the whole grid view. How do i do that?

This can be done easily in a GridView by using the HeaderImageUrl property on the column.
For Example:
<asp:GridView ID="GridView1" runat="server">
<Columns>
<asp:BoundField HeaderImageUrl="icon.png" />
<asp:TemplateField HeaderImageUrl="icon.png" />
</Columns>
</asp:GridView>

Binding a Button to a GridView

This a pretty simple question, I'm just not sure how to do it exactly. I would like to bind a Button or perhaps ImageButton to a GridView in ASP.NET/C#. Currently, the GridView has two columns and is bound to a DataTable with two columns. I want to add a third column to the GridView, which will include the Button.
I know GridView has ButtonField, but I'm not too sure how to go about using it to do what I want. I want to dynamically generate these Buttons and add them to the GridView.
Here is how my GridView looks right now:
<asp:GridView
ID="GridView1"
Runat="server">
<Columns>
<asp:HyperLinkField
HeaderText="Display Name"
DataNavigateUrlFields="DISPNAME"
DataNavigateUrlFormatString="ViewItem.aspx"
DataTextField="DISPNAME">
<ItemStyle Width="70%" />
</asp:HyperLinkField>
<asp:BoundField
DataField="TypeDisp"
HeaderText="Type">
<ItemStyle Width="20%" />
</asp:BoundField>
</Columns>
</asp:GridView>

You can use a template field like the following,
<TemplateField>
<ItemTemplate>
<asp:ImageButton ImageUrl="image url" CommandName="SomeCommand" CommandArgument='<%# Eval("Id") %>'/>
</ItemTemplate>
</TemplateField>
Then you can handle the RowCommand event of the GridView and check the e.CommandName to see what command to be executed and you can get the e.CommandArgument as well which could be the row Id like I used in the code above.

If we are talking a button that's always present, you can use ButtonField, or even use a TemplateField and provide the template with the button, and bind the data to the button (sounds like you may want to bind data to the attributes of the button?)
If you are looking to dynamically generate buttons in the UI, tap into the RowCreated event and add the button the GridView. You'd have to do this on every page load; the GridView won't remember a button created programmatically.
HTH.

Gridview Column Removing

I have a web application that I am working on(ASP.NET 2.0 C#). In it I have a GridView whose data source is an Oracle database. I get the data into the gridview in my codebehind, and don't set the datasource directly.
I wanted to create a hyperlink field (NAME) that takes me to a details page about a specific record. What ends up happening is that it creates the Hyperlink field as well as the regular field that it gets from the datasource, which I don't want. If I remove the field from my SELECT statement, it gives an error saying something like: "NAME" not found in datasource.
How can I eliminate the regular field, and get a hyperlink field instead? I have tried Gridview.Columns.Remove(columnlocation), but that won't work coz the columns don't exist there originally.
Please Help
Thank you.

Instead of removing columns, disable AutoGenerateColumns property of the gridview and set your hyperlink column manually like that :
<asp:gridview id="GridView1"
autogeneratecolumns="false"
runat="server">
<asp:HyperLinkField DataNavigateUrlFields="UserID"
DataNavigateUrlFormatString="UserDetails.aspx?id={0}"
DataTextField="UserName" />
</asp:gridview>

Sounds like you have AutoGenerateColumns property set to TRUE on your grid. This means that a column is generated for EVERY column you return from your query.
If you want to have some custom columns, you should set AutoGenerateColumns="false" and add all the columns to the GirdView as asp:BoundField and your Hyperlink column as asp:TemplateField
Let me know if I'm off the mark with this
here's some code:
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False">
<Columns>
<asp:BoundField DataField="Name" />
<asp:BoundField DataField="Whatever" />
<asp:TemplateField>
<ItemTemplate>
<a href='<%# Eval("UserId", "URL_TO_USER?userId={0}") %>'>Details</a>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>