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Grid view is not being refreshed on exporting grid view to excel in asp.net

i am come up with scenario that while exporting grid view to excel its not refreshing my grid data source. Below is my code what i have done before. Below code is updating flag in database and then trying to refresh the grid data source in Fill Grid method.
protected void Process_Command(object sender, CommandEventArgs e)
{
if (!string.IsNullOrEmpty(Convert.ToString(e.CommandArgument)))
{
using (var transaction = context.Database.BeginTransaction())
{
DocumentOGP objDocumentOGP = context.DocumentOGPs.Find(Convert.ToInt64(e.CommandArgument));
objDocumentOGP.UpdationDate = DateTime.Now;
objDocumentOGP.DispatchStatusID = 2;
context.DocumentOGPs.Add(objDocumentOGP);
context.Entry(objDocumentOGP).State = System.Data.Entity.EntityState.Modified;
context.SaveChanges();
transaction.Commit();
FillGrid();
}
ExportToExcel(Convert.ToInt64(e.CommandArgument));
}
}
Below is the Export to excel method.
public void ExportToExcel(Int64 OGPCode)
{
DataTable dtPickList =GeneralQuery.GetDocumentPickList(OGPCode);
if (dtPickList != null && dtPickList.Rows.Count>0)
{
//Create a dummy GridView
GridView GridView1 = new GridView();
GridView1.AllowPaging = false;
GridView1.DataSource = dtPickList;
GridView1.DataBind();
Response.Clear();
Response.Buffer = true;
Response.AddHeader("content-disposition", "attachment;filename=Inbox.xls");
Response.Charset = "";
Response.ContentType = "application/vnd.ms-excel";
StringWriter sw = new StringWriter();
HtmlTextWriter hw = new HtmlTextWriter(sw);
for (int i = 0; i < GridView1.Rows.Count; i++)
{
//Apply text style to each Row
GridView1.Rows[i].Attributes.Add("class", "textmode");
}
GridView1.RenderControl(hw);
//style to format numbers to string
string style = #"<style> .textmode { mso-number-format:\#; } </style>";
Response.Write(style);
Response.Output.Write(sw.ToString());
Response.Flush();
Response.End();
GridView1.DataSource = null;
Response.Write(Request.RawUrl.ToString());
}
}
public override void VerifyRenderingInServerForm(Control control)
{
}
Please help me what i am doing wrong. Thanks

Finally i found the way to refresh the grid view while exporting the grid view to excel. I just create new web form and put ExportGridToExcel() method in Page_Load and on button click it refresh the grid view data source and open new tab to download excel file. Below is my code.
protected void Process_Command(object sender, CommandEventArgs e)
{
if (Session["Status"] != "Refreshed")
{
if (!string.IsNullOrEmpty(Convert.ToString(e.CommandArgument)))
{
using (var transaction = context.Database.BeginTransaction())
{
DocumentOGP objDocumentOGP = context.DocumentOGPs.Find(Convert.ToInt64(e.CommandArgument));
objDocumentOGP.UpdationDate = DateTime.Now;
objDocumentOGP.DispatchStatusID = 2;
context.DocumentOGPs.Add(objDocumentOGP);
context.Entry(objDocumentOGP).State = System.Data.Entity.EntityState.Modified;
context.SaveChanges();
transaction.Commit();
FillGrid();
Session["OGPCode"] = Convert.ToString(e.CommandArgument);
}
ScriptManager.RegisterStartupScript(Page, Page.GetType(), "OpenWindow", "window.open('http://localhost:56430/DownLoadExcel','_newtab');", true);
}
}
}
Below is my Download excel file web-form and its implementation
public partial class DownLoadExcel : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
if (!string.IsNullOrEmpty(Convert.ToString(Session["OGPCode"])))
{
ExportToExcel(Convert.ToInt64(Session["OGPCode"]));
Session["OGPCode"] = null;
}
}
}
public void ExportToExcel(Int64 OGPCode)
{
DataTable dt = GeneralQuery.GetDocumentPickList(OGPCode);
//create a new byte array
byte[] bin;
string FileName = "Pick-List-" + DateTime.Now.ToString();
//create a new excel document
using (ExcelPackage excelPackage = new ExcelPackage())
{
//create a new worksheet
ExcelWorksheet ws = excelPackage.Workbook.Worksheets.Add(FileName);
//add the contents of the datatable to the excel file
ws.Cells["A1"].LoadFromDataTable(dt, true);
//auto fix the columns
ws.Cells[ws.Dimension.Address].AutoFitColumns();
//loop all the columns
for (int col = 1; col <= ws.Dimension.End.Column; col++)
{
//make all columns just a bit wider, it would sometimes not fit
ws.Column(col).Width = ws.Column(col).Width + 1;
var cell = ws.Cells[1, col];
//make the text bold
cell.Style.Font.Bold = true;
//make the background of the cell gray
var fill = cell.Style.Fill;
fill.PatternType = ExcelFillStyle.Solid;
fill.BackgroundColor.SetColor(ColorTranslator.FromHtml("#BFBFBF"));
//make the header text upper case
cell.Value = ((string)cell.Value).ToUpper();
}
//convert the excel package to a byte array
bin = excelPackage.GetAsByteArray();
}
//clear the buffer stream
Response.ClearHeaders();
Response.Clear();
Response.Buffer = true;
//set the correct contenttype
Response.ContentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
//set the correct length of the data being send
Response.AddHeader("content-length", bin.Length.ToString());
//set the filename for the excel package
Response.AddHeader("content-disposition", "attachment; filename=\"" + FileName + ".xlsx\"");
//send the byte array to the browser
Response.OutputStream.Write(bin, 0, bin.Length);
//cleanup
Response.Flush();
HttpContext.Current.ApplicationInstance.CompleteRequest();
}
}

When you update GridView or any control values dynamically you should render and export it to other application.
Sample: check with RenderControl method of GridView.
private void ExportGridToExcel()
{
Response.Clear();
Response.Buffer = true;
Response.ClearContent();
Response.ClearHeaders();
Response.Charset = "";
string FileName = "xyz.xls";
StringWriter strwritter = new StringWriter();
HtmlTextWriter htmltextwrtter = new HtmlTextWriter(strwritter);
Response.Cache.SetCacheability(HttpCacheability.NoCache);
Response.ContentType = "application/vnd.ms-excel";
Response.AddHeader("Content-Disposition", "attachment;filename=" + FileName);
GridView1.RenderControl(htmltextwrtter);
Response.Write(strwritter.ToString());
Response.End();
}

Export current gridview data

I'm using this code to export my gridview data. I have a dropdown in my page and when I select dropdown values the data changes in gridview and I need to export only that present data into excel.
protected void ExporttoExcel(object sender, EventArgs e)
{
Response.Clear();
Response.AddHeader("content-disposition", "attachment; filename=Report.xls");
Response.ContentType = "application/vnd.xls";
System.IO.StringWriter stringWrite = new System.IO.StringWriter();
System.Web.UI.HtmlTextWriter htmlWrite = new HtmlTextWriter(stringWrite);
GridView1.RenderControl(htmlWrite);
Response.Write(stringWrite.ToString());
Response.End();
}
I am using paging and when I export initially without having selected dropdown values I need to export all the data, but now only the datas in the first page alone gets exported.
Can anyone correct me where I'm wrong?

I have a custom made method for exporting excels in a formatted style from a Datatable-Gridvieww. You can use it, by assigning to the table variable your Datatable in which you bind the Gridview( the whole datatable before the paging)
private void ExportToExcel(DataTable table, GridView gv)
{
Response.ClearContent();
Response.Charset = your charset//"Windows-1253";
Response.ContentEncoding = your encoding//Encoding.UTF8;
string attachment = "attachment; filename=test.xls";
Response.AddHeader("content-disposition", attachment);
Response.ContentType = "application/ms-excel";
HttpContext.Current.Response.Write(#"<!DOCTYPE HTML PUBLIC ""-//W3C//DTD HTML 4.0 Transitional//EN"">");
HttpContext.Current.Response.Write("<font style='font-size:10.0pt; font-family:Calibri;'>");
HttpContext.Current.Response.Write("<BR><BR><BR>");
HttpContext.Current.Response.Write("<Table border='1' bgColor='#ffffff' " +
"borderColor='#000000' cellSpacing='0' cellPadding='0' " +
"style='font-size:10.0pt; font-family:Calibri; background:white;'> <TR>");
int columnscount = table.Columns.Count;
for (int j = 0; j < columnscount; j++)
{
HttpContext.Current.Response.Write("<Td style='background-color: #C0C0C0;' align=" + "center" + ">");
HttpContext.Current.Response.Write("<B>");
HttpContext.Current.Response.Write(table.Columns[j].ToString());
HttpContext.Current.Response.Write("</B>");
HttpContext.Current.Response.Write("</Td>");
}
HttpContext.Current.Response.Write("</TR>");
foreach (DataRow row in table.Rows)
{
HttpContext.Current.Response.Write("<TR>");
for (int i = 0; i < table.Columns.Count; i++)
{
HttpContext.Current.Response.Write("<Td align=" + "center" + ">"); ;
HttpContext.Current.Response.Write(row[i].ToString());
HttpContext.Current.Response.Write("</Td>");
}
HttpContext.Current.Response.Write("</TR>");
}
HttpContext.Current.Response.Write("</Table>");
HttpContext.Current.Response.Write("</font>");
HttpContext.Current.Response.Flush();
HttpContext.Current.Response.End();
}

You can save the SQL query result in a DataTable and save that DataTable in a ViewState or session. Then when clicking the export button, retrieve the DataTable from the ViewState and create a dummy GridView that will have the DataTable as its source.
Something like this:
protected void ExporttoExcel(object sender, EventArgs e)
{
//First, retrieve the DataTable from ViewState
DataTable Dt = new DataTable();
Dt = (DataTable)ViewState["DtData"];
//Now you have the data, create a dummy GridView that will be used for exporting
GridView grdView = new GridView();
grdView.AllowPaging = false;
grdView.DataSource = Dt;
grdView.DataBind();
//Do the Exporting stuff
Response.Clear();
Response.AddHeader("content-disposition", "attachment; filename=Report.xls");
Response.ContentType = "application/vnd.xls";
System.IO.StringWriter stringWrite = new System.IO.StringWriter();
System.Web.UI.HtmlTextWriter htmlWrite = new HtmlTextWriter(stringWrite);
grdView.RenderControl(htmlWrite);
Response.Write(stringWrite.ToString());
Response.End();
}
This way, each time you change the dropdownlist value, save the selected SQL query result in a datatable and then in the ViewState and export.
Of course, if you can update your question with the dropdownlist code or how are you setting the GridView datasource, I'd update this answer.
Hope this helps.

Disable the GridView paging then render. You may need to do the binding as well.
protected void ExporttoExcel(object sender, EventArgs e)
{
Response.Clear();
Response.AddHeader("content-disposition", "attachment; filename=Report.xls");
Response.ContentType = "application/vnd.xls";
System.IO.StringWriter stringWrite = new System.IO.StringWriter();
System.Web.UI.HtmlTextWriter htmlWrite = new HtmlTextWriter(stringWrite);
// ************************
GridView1.AllowPaging = false; // <- disable paging then render
// also do the binding
GridView1.DataSource = myDataSource;
GridView1.DataBind();
// ************************
GridView1.RenderControl(htmlWrite);
Response.Write(stringWrite.ToString());
Response.End();
}
Edit (working example)
ASPX (GridView and an export Button):
<asp:GridView ID="grd1" runat="server" AllowPaging="true" PageSize="10" AutoGenerateColumns="false" OnPageIndexChanging="grd1_PageIndexChanging">
<Columns>
<asp:BoundField DataField="StudentID" HeaderText="Student ID" />
<asp:BoundField DataField="StudentName" HeaderText="Student Name" />
<asp:BoundField DataField="FatherName" HeaderText="Father Name" />
</Columns>
</asp:GridView>
<asp:Button ID="btnExport" runat="server" Text="Export" OnClick="btnExport_Click" />
Code Behind:
protected void Page_Load(object sender, EventArgs e)
{
if (!this.IsPostBack)
{
this.BindGridView();
}
}
private void BindGridView()
{
using (var dtStudent = this.GetStudentData())
{
this.grd1.DataSource = dtStudent;
this.grd1.DataBind();
}
}
private DataTable GetStudentData()
{
var dtStudent = new DataTable();
dtStudent.Columns.Add("StudentID");
dtStudent.Columns.Add("StudentName");
dtStudent.Columns.Add("FatherName");
for (int i = 0; i < 20; i++)
{
var sIndex = i.ToString("00");
dtStudent.Rows.Add("Student-" + sIndex, "Name-" + sIndex, "Father-" + sIndex);
}
return dtStudent;
}
protected void grd1_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
this.grd1.PageIndex = e.NewPageIndex;
this.BindGridView();
}
protected void ExporttoExcel()
{
Response.Clear();
Response.AddHeader("content-disposition", "attachment; filename=Report.xls");
Response.ContentType = "application/vnd.xls";
System.IO.StringWriter stringWrite = new System.IO.StringWriter();
System.Web.UI.HtmlTextWriter htmlWrite = new HtmlTextWriter(stringWrite);
// ************************
this.grd1.AllowPaging = false; // <- disable paging then render
this.BindGridView();
// ************************
this.grd1.RenderControl(htmlWrite);
Response.Write(stringWrite.ToString());
Response.End();
}
public override void VerifyRenderingInServerForm(Control control)
{
//base.VerifyRenderingInServerForm(control);
}
protected override void Render(HtmlTextWriter writer)
{
if (this._Export)
this.ExporttoExcel();
else
base.Render(writer);
}
private bool _Export = false;
protected void btnExport_Click(object sender, EventArgs e)
{
this._Export = true;
}

data transfer gird view to excel sheet

data transfer grid view to excel in asp dot net code is run but blank sheet generate of excel but data is not loaded in excel sheeet how to solve this type of broblem
protected void btnexcel_Click1(object sender, EventArgs e)
{
Response.Clear();
Response.Buffer = true;
Response.AddHeader("content-disposition",
"attachment;filename=ActualsAndBudgets.xls");
Response.Charset = "";
Response.ContentType = "application/ms-excel";
Response.Cache.SetCacheability(HttpCacheability.NoCache);
StringWriter sw = new StringWriter();
HtmlTextWriter htw = new HtmlTextWriter(sw);
gvdetails.AllowPaging = false;
gvdetails.DataBind();
gvdetails.RenderControl(htw);
Response.Write(sw.ToString());
Response.End();
}
public override void VerifyRenderingInServerForm(Control control)
{
}

Check for data in the gridview, your data is not getting binded. So the excel is empty. Debug and check for data inside the gridview. It should work.
Try with this one
Response.Clear();
Response.Buffer = true;
Response.AddHeader("content-disposition",
"attachment;filename=ActualsAndBudgets.xls");
Response.Charset = "";
Response.ContentType = "application/ms-excel";
Response.Cache.SetCacheability(HttpCacheability.NoCache);
StringWriter sw = new StringWriter();
HtmlTextWriter htw = new HtmlTextWriter(sw);
GridView1.RenderControl(htw);
Response.Write(sw.ToString());
Response.End();

may be problem in data binding in export excel .
check that data properly bin to a gridview or not.
Use this code for export grid view in excel sheet and note that you must add iTextSharp dll in you project.
protected void btnExportExcel_Click(object sender, EventArgs e)
{
Response.Clear();
Response.Buffer = true;
Response.AddHeader("content-disposition", "attachment;filename=GridViewExport.xls");
Response.Charset = "";
Response.ContentType = "application/vnd.ms-excel";
StringWriter sw = new StringWriter();
HtmlTextWriter hw = new HtmlTextWriter(sw);
GridView1.AllowPaging = false;
// Re-Bind data to GridView
using (CompMSEntities1 CompObj = new CompMSEntities1())
{
Start = Convert.ToDateTime(txtStart.Text);
End = Convert.ToDateTime(txtEnd.Text);
GridViewSummaryReportCategory.DataSource = CompObj.SP_Category_Summary(Start, End);
SP_Category_Summary_Result obj1 = new SP_Category_Summary_Result();
GridView1.DataBind();
GridView1.Visible = true;
ExportTable.Visible = true;
}
//Change the Header Row back to white color
GridView1.HeaderRow.Style.Add("background-color", "#FFFFFF");
GridView1.Style.Add(" font-size", "10px");
//Apply style to Individual Cells
GridView1.HeaderRow.Cells[0].Style.Add("background-color", "green");
GGridView1.HeaderRow.Cells[1].Style.Add("background-color", "green");
GridView1.HeaderRow.Cells[2].Style.Add("background-color", "green");
GridView1.HeaderRow.Cells[3].Style.Add("background-color", "green");
GridView1.HeaderRow.Cells[4].Style.Add("background-color", "green");
for (int i = 1; i < GridView1.Rows.Count; i++)
{
GridViewRow row = GridView1.Rows[i];
//Change Color back to white
row.BackColor = System.Drawing.Color.White;
//Apply text style to each Row
// row.Attributes.Add("class", "textmode");
//Apply style to Individual Cells of Alternating Row
if (i % 2 != 0)
{
row.Cells[0].Style.Add("background-color", "#C2D69B");
row.Cells[1].Style.Add("background-color", "#C2D69B");
row.Cells[2].Style.Add("background-color", "#C2D69B");
row.Cells[3].Style.Add("background-color", "#C2D69B");
row.Cells[4].Style.Add("background-color", "#C2D69B");
}
}
GridView1.RenderControl(hw);
//style to format numbers to string
string style = #"<style> .textmode { mso-number-format:\#; } </style>";
Response.Write(style);
Response.Output.Write(sw.ToString());
Response.Flush();
Response.End();
}

ASP.Net Grid Export to Excel

I am using following code to export my GridView to Excel:
string attachment = "attachment; filename=Contacts.xls";
Response.ClearContent();
Response.AddHeader("content-disposition", attachment);
Response.ContentType = "application/ms-excel";
StringWriter sw = new StringWriter();
HtmlTextWriter htw = new HtmlTextWriter(sw);
gvReports.RenderControl(htw);
Response.Write(sw.ToString());
Response.End();
This code is copied from this site. I have followed all the instructions but after executing nothing happened. No exception (Except Thread.Abort which is, I think, because of Response.End()).
I have also used Response.Flush() BUT nothing is happening no exception or file etc.
Thanks.
EDIT Now Code Is like following:
My GridView is in Control. The control is on asp.net page and that page has following method.
public override void VerifyRenderingInServerForm(Control control)
{
}
Click event of button in ascx control:
protected void btnExportToExcel_Click(object sender, EventArgs e)
{
ExportToExcel();
}
private void ExportToExcel()
{
Response.Clear();
Response.Buffer = true;
Response.AddHeader("content-disposition",
"attachment;filename=GridViewExport.xls");
Response.Charset = "";
Response.ContentType = "application/vnd.ms-excel ";
StringWriter sw = new StringWriter();
HtmlTextWriter hw = new HtmlTextWriter(sw);
gvReports.AllowPaging = false;
gvReports.DataBind();
gvReports.RenderControl(hw);
Response.Output.Write(sw.ToString());
Response.Flush();
Response.End();
}
gvReports has no link, checkbox etc. 5 bound columns and 1 button.
Nothing is happening.

itextsharp dlls ,you will get the best method to do that
Click here

I'm using MVC3 for my solution, but the code I'm using to push data out to an excel file is:
var grid = new GridView
{
DataSource = from lineItem in rows
select new
{
lineItem.ProjectName,
lineItem.Sat,
lineItem.Sun,
lineItem.Mon,
lineItem.Tue,
lineItem.Wed,
lineItem.Thu,
lineItem.Fri
}
};
var fileName = string.Format("{0}:{1}", userName, timesheetDate);
grid.DataBind();
Response.ClearContent();
Response.AddHeader("content-disposition", "attachment; filename=" + fileName + ".xls");
Response.ContentType = "application/msexcel";
var sw = new StringWriter();
var htw = new HtmlTextWriter(sw);
grid.RenderControl(htw);
Response.Write(sw.ToString());
Response.End();
The immediate differences that I see are:
I take my data and create a new GridView
Response.ClearContent() instead of a Response.Clear()
Response.Write instead of Response.Output.Write
Everything else looks the same, and we both are using a click event to call a void function. So I'm guessing that if you make those few changes, your code should start working for you.
It's been a while since I implemented this solution and I couldn't find the sites that I got this off of so I can't show you my original sources. Sorry about that.

UserControl code:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.IO;
public partial class WebUserControl : System.Web.UI.UserControl
{
protected void Page_Load(object sender, EventArgs e)
{
this.gridView.DataSource = this.SqlDataSource1;
this.gridView.DataBind();
}
private void excel_Export()
{
Response.Clear();
Response.Buffer = true;
Response.AddHeader("content-disposition",
"attachment;filename=GridViewExport.xls");
Response.Charset = "";
Response.ContentType = "application/vnd.ms-excel ";
StringWriter sw = new StringWriter();
HtmlTextWriter hw = new HtmlTextWriter(sw);
this.gridView.AllowPaging=false;
this.gridView.DataBind();
this.gridView.RenderControl(hw);
Response.Output.Write(sw.ToString());
Response.Flush();
Response.End();
}
protected void Button1_Click(object sender, EventArgs e)
{
excel_Export();
}
}
User Control Hosting page:
<asp:Content ID="BodyContent" runat="server" ContentPlaceHolderID="MainContent">
<uc1:WebUserControl ID="WebUserControl1" runat="server" />
</asp:Content>
You really dont need following event in code behind of User control hosting page, because excel export is being done via user control which contains grid view and button.
public override void VerifyRenderingInServerForm(Control control)
{
/* Verifies that the control is rendered */
}
Hopefully this will you help to solve the issue.

Column Values Customisation- Export Excel in ASP.NET

I have to export gridview in to the excel sheet 2003. With my code I can Export the data into eXcel Sheet directly. But If there is a null value for the column, Then how do I replace with empty string in Excel sheet. There is a date column which is null, is there any event handler that occurs between export button click and the loading the data into excel. If there is one I can compare the values in the database and can replace the null value with empty String. in the evnt handler.
Please point me in right direction.
Thank you

On click of the export button, you can iterate through your grid rows and replace whatever you need. For example, the code below will replace : with .:
protected void btnExport_Click(object sender, EventArgs e)
{
StringWriter sw = new StringWriter();
HtmlTextWriter htw = new HtmlTextWriter(sw);
string attachment = "attachment; filename=SummaryReport" + DateTime.Now.ToString() + ".xls";
Response.ClearContent();
Response.AddHeader("content-disposition", attachment);
Response.ContentType = "application/ms-excel";
foreach (GridViewRow grdRow in grdProjectTasks.Rows)
{
Label lblActualDuration = (Label)grdRow.FindControl("lblActualDuration");
lblActualDuration.Text = lblActualDuration.Text.Replace(":", ".");
}
grdProjectTasks.RenderControl(htw);
Response.Write(sw.ToString());
Response.End();
}