Exporter la Grille vue d'excel et enregistrer le fichier excel dans le dossier

Vous pouvez faire ceci:

private void ExportGridView()
{
    System.IO.StringWriter sw = new System.IO.StringWriter();
    System.Web.UI.HtmlTextWriter htw = new System.Web.UI.HtmlTextWriter(sw);

    //Render grid view control.
    gvFiles.RenderControl(htw);

    //Write the rendered content to a file.
    string renderedGridView = sw.ToString();
    System.IO.File.WriteAllText(@"C:\Path\On\Server\ExportedFile.xlsx", renderedGridView);
}

public partial class exportgridtoexcel : System.Web.UI.Page
{
    SqlConnection con=new SqlConnection(ConfigurationManager.ConnectionStrings["dbconnection"].ConnectionString.ToString());
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!Page.IsPostBack)
        {
            GetData();
        }
    }
    public void GetData()
    {
        SqlDataAdapter sda = new SqlDataAdapter("select * from EmpData", con);
        DataTable dt = new DataTable();
        sda.Fill(dt);
        GridView1.DataSource = dt;
        GridView1.DataBind();
    }

    protected void btnDownload_Click(object sender, EventArgs e)
    {
        GetData();
        exporttoexcel("Report.xls", GridView1);
        GridView1 = null;
        GridView1.Dispose();



    }
    public void exporttoexcel(string filename,GridView gv)
    {
        Response.ClearContent();
        Response.AddHeader("content-disposition", "attachment;filename=" + filename);
        Response.ContentType = "applicatio/excel";
        StringWriter sw = new StringWriter(); ;
        HtmlTextWriter htm=new HtmlTextWriter(sw);
        gv.RenderControl(htm);
        Response.Write(sw.ToString());
        Response.End();
    }
    public override void VerifyRenderingInServerForm(Control control)
    {

    }
}

}

Folowed le lien: C# fichier Excel OLEDB lire l'IMPORTATION HTML

Utiliser le Extended Properties=\"HTML Import;HDR=No;IMEX=1 the select * from [tablename],
tablename est retourné à partir de GetOleDbSchemaTable.

Remarque: Ce ne serait pas la charge de la normale excel. Pour que l'utilisation Extended Properties=\"Excel 8.0;HDR=No;IMEX=1\, où le nom de la table sera avec $ signe.

Vérifier exemple de code:
Ne peut pas lire de fichier excel après la création de ce Fichier à l'aide de.WriteAllText() la fonction

d'abord ajouter EPPLUS bibliothèque de référence en application et les ajouter à l'aide OfficeOpenXml;

//d'affaires de la classe d'objet

classe bocls
{

    string name;

    public string NAME
    {
        get { return name; }
        set { name = value; }
    }
    string id;

    public string ID
    {
        get { return id; }
        set { id = value; }
    }



    public bocls() { }
    public bocls(string name, string id)
    {
        this.name = name;
        this.id = id;         

    }

//à l'exportation l'événement clic du bouton

protected void lbtnExport_Click(object sender, EventArgs e)
{

            List<bocls> list6 =  new List<bocls>();
//copy the grid view values into list
list6 = (from row in dataGridView1.Rows.Cast<DataGridViewRow>()
from cell in row.Cells.Cast<DataGridViewCell>()
select new 
{
//project into your new class from the row and cell vars.
}).ToList();
}
ExcelPackage excel = new ExcelPackage();
var workSheet = excel.Workbook.Worksheets.Add("Products");
var totalCols = GridView1.Rows[0].Cells.Count;
var totalRows = GridView1.Rows.Count;
var headerRow = GridView1.HeaderRow;
for (var i = 1; i <= totalCols; i++)
{
workSheet.Cells[1, i].Value = headerRow.Cells[i - 1].Text;
}
for (var j = 1; j <= totalRows; j++)
{
for (var i = 1; i <= totalCols; i++)
{
var item = list6.ElementAt(j - 1);
workSheet.Column(1).Width = 13;
workSheet.Column(2).Width = 10;
workSheet.Cells[j + 1, i].Style.WrapText = true;
if (headerRow.Cells[i - 1].Text == "ID")
workSheet.Cells[j + 1, i].Value = item.GetType().GetProperty("id").GetValue(item, null);
else if (headerRow.Cells[i - 1].Text == "NAME")
workSheet.Cells[j + 1, i].Value = item.GetType().GetProperty("name").GetValue(item, null);
workSheet.Cells[j + 1, i].Value = workSheet.Cells[j + 1, i].Value.ToString().Replace("<br/>", "");
}
}
using (var memoryStream = new MemoryStream())
{
Response.ContentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
string filename = Guid.NewGuid().ToString() + ".xlsx";
Response.AddHeader("content-disposition", "attachment;  filename=" + filename);
excel.SaveAs(memoryStream);   
//add your destination folder
FileStream fileStream = new FileStream(@"C:\Users\karthi\Downloads\New folder\" + filename, FileMode.Create,FileAccess.Write,FileShare.Write);
memoryStream.WriteTo(fileStream);
fileStream.Close();
memoryStream.WriteTo(Response.OutputStream);
memoryStream.Close();
memoryStream.WriteTo(Response.OutputStream);
Response.Flush();
Response.End();
}
}