Unable to format date in dataset column,GridView - asp.net

Question

I am reading data from an excel sheet and displaying it in a data gridview.There are some date columns in the excel.So when i read the data from the excel and bind it to the dataGridView.The date is displayed in the format "02/02/2009 12:00:00 AM" but the actual data in the excel column is in the format "2/2/2009".So how to change the date format in the datagridview.
Since i am binding the data from the dataset i dont have any template columns or bound column set so i dont know where to set the HtmlEncode="False" DataFormatString = "{0:T}"
Is there any way to do this.Please help me.
Please find the below code sample.
string OleDbConnection = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source= "+ FileUpload1.PostedFile.FileName + ";Extended Properties=\"Excel 8.0;HDR=Yes;IMEX=1\"";
string strSheetName = "Sheet1";
OleDbConnection oledbConnection;
OleDbCommand oledbCommand;
OleDbDataAdapter oledbAdapter;
oledbCommand = new OleDbCommand();
oledbAdapter = new OleDbDataAdapter();
DataSet dsExcellData = new DataSet();
oledbConnection = new OleDbConnection(OleDbConnection);
oledbConnection.Open();
oledbCommand.Connection = oledbConnection;
oledbCommand.CommandText = "Select * from [" + strSheetName + "$]"; // i want to find this sheet name
oledbAdapter.SelectCommand = oledbCommand;
oledbAdapter.Fill(dsExcellData);
oledbConnection.Close();
GridView1.DataSource = dsExcellData.Tables[0];
GridView1.DataBind();
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I tried the
dsExcellData.Tables[0].Rows[rowcount]["date_column"].ToString()] = dsExcellData.Tables[0].Rows[rowcount]["date_column"].ToString()].ToString("d");
but the value is not getting assigned as "mm/dd/yyyy" It is also taking the time default time again (mm/dd/yyyy hh:mm:ss AM).
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I am just assigning the data set to the gridview.The problem is the dataset is reading the date column in the format mm/dd/yyyy hh:mm:ss AM.I am unable to change the data in the dataset also.
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Finaly i got the answer from ScottE:
we have to add the below code in the itemdatabound of the datagridview :
protected void dgValidatedData_ItemDataBound1(object sender, DataGridItemEventArgs e)
{
for (int i = 0; i <= e.Item.Cells.Count - 1; i++)
{
System.DateTime cellDate = default(System.DateTime);
if (System.DateTime.TryParse(e.Item.Cells[i].Text, out cellDate))
{
e.Item.Cells[i].Text = string.Format("{0:d}", cellDate);
}
}
}

Answer 1

Ok, try this, where "Item" is the column name (could be multiple) that is a date that needs formatting. This is of course vb.net, but you can sort that out. I'm sure there's a better way, but this works.
Protected Sub gv_RowDataBound(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewRowEventArgs)
If e.Row.RowType = DataControlRowType.DataRow Then
For i As Integer = 0 To e.Row.Cells.Count - 1
If gv.HeaderRow.Cells(i).Text = "Item" Then
e.Row.Cells(i).Text = String.Format("{0:d}", CType(e.Row.Cells(i).Text, Date))
End If
Next
End If
End Sub
Or, if you don't know what columns will have dates, the following will work as well:
Protected Sub gv_RowDataBound(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewRowEventArgs)
If e.Row.RowType = DataControlRowType.DataRow Then
For i As Integer = 0 To e.Row.Cells.Count - 1
Dim cellDate As Date
If Date.TryParse(e.Row.Cells(i).Text, cellDate) Then
e.Row.Cells(i).Text = String.Format("{0:d}", cellDate)
End If
Next
End If
End Sub

Answer 2

If you're binding it as a asp:BoundField you'll need to set htmlencode to false.
<asp:BoundField HtmlEncode="false" DataField="Blah" DataFormatString="{0:d}" />

Answer 3

Date format you should define in your GridView column. For example:
<asp:GridView>
...
<asp:TemplateField>
<ItemTemplate>
<asp:Label ID="Label1" runat="server" Text='<%# Eval("Date", "{0:T}") %>'></asp:Label>
</ItemTemplate>
...
</asp:GridView>

Answer 4

Here is a solution using a custom control that derives from GridView:
using System;
using System.Collections;
using System.Web.UI.WebControls;
namespace CustomControls {
public class FormattedGridView : GridView {
protected override ICollection CreateColumns(PagedDataSource dataSource, bool useDataSource) {
// Call base method and return the collection as an ArrayList
var columns = (ArrayList) base.CreateColumns(dataSource, useDataSource);
for (var i = 0; i < columns.Count; i++) {
var agf = columns[i] as AutoGeneratedField;
if (agf != null && agf.DataType == typeof(DateTime)) {
// create a new column because the AutoGeneratedField does not support
// the modification of the DataFormatString property
var bf = new BoundField();
// copy some of the original properties
bf.DataField = agf.DataField;
bf.HeaderText = agf.HeaderText;
bf.HtmlEncode = false;
// set the format for the DateTime types
bf.DataFormatString = "{0:T}";
// replace the existing auto-generated colums
columns[i] = bf;
}
}
return columns;
}
}
}

Answer 5

Finaly i got the answer from ScottE:
we have to add the below code in the itemdatabound of the datagridview :
protected void dg_ItemDataBound1(object sender, DataGridItemEventArgs e)
{
for (int i = 0; i <= e.Item.Cells.Count - 1; i++)
{
System.DateTime cellDate = default(System.DateTime);
if (System.DateTime.TryParse(e.Item.Cells[i].Text, out cellDate))
{
e.Item.Cells[i].Text = string.Format("{0:d}", cellDate);
}
}
}
But the above code will check all the data that is bound to the datagrig.It will try to parse the data as datetime in the cell.If it is a valid datetime then it will convert the data into the format which we applied.