How to set image size in excel while exporting GridView to excel in ASP.Net

Hi chukaeke,

I have created sample code which fullfill your requirement.Please refer carefully and Implement in your code.

HTML

<form id="form1" runat="server">
<asp:FileUpload ID="FileUpload1" runat="server" />
<asp:Button ID="btnUpload" runat="server" Text="Upload" OnClick="btnUpload_Click" />
<div>
    <asp:GridView ID="gridInformation" runat="server" AutoGenerateColumns="false" Font-Names="Arial"
        OnRowDataBound="gridInformation_RowDataBound">
        <Columns>
            <asp:BoundField DataField="ID" HeaderText="ID" />
            <asp:BoundField DataField="FileName" HeaderText="Image Name" />
            <asp:TemplateField HeaderText="Pics" ItemStyle-Height="100" ItemStyle-Width="100">
                <ItemTemplate>
                    <asp:Label ID="lblPath" Visible="false" Text='<%#Eval("FilePath") %>' runat="server" />
                    <asp:Image ID="empimage" runat="server" ImageUrl='<%# Eval("FilePath", GetUrl("{0}")) %>' />
                </ItemTemplate>
            </asp:TemplateField>
        </Columns>
    </asp:GridView>
    <br />
    <asp:Button ID="btnExportExcel" CommandArgument="Excel" runat="server" Text="Export-Excel"
        OnClick="Export_Grid" />
</div>
</form>

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
        this.GetImage();
    }
}

private void GetImage()
{
    DataTable dt = new DataTable();
    String strConnString = System.Configuration.ConfigurationManager.ConnectionStrings["conString"].ConnectionString;
    string strQuery = "select * from [Images]";
    SqlCommand cmd = new SqlCommand(strQuery);
    SqlConnection con = new SqlConnection(strConnString);
    SqlDataAdapter sda = new SqlDataAdapter();
    cmd.CommandType = CommandType.Text;
    cmd.Connection = con;
    try
    {
        con.Open();
        sda.SelectCommand = cmd;
        sda.Fill(dt);
        gridInformation.DataSource = dt;
        gridInformation.DataBind();
    }
    catch (Exception ex)
    {
        Response.Write(ex.Message);
    }
    finally
    {
        con.Close();
        sda.Dispose();
        con.Dispose();
    }
}

protected void btnUpload_Click(object sender, EventArgs e)
{
    if (FileUpload1.PostedFile != null)
    {

        string FileName = Path.GetFileName(FileUpload1.PostedFile.FileName);

        //Save files to disk Temp.
        FileUpload1.SaveAs(Server.MapPath("Images/" + FileName));

        //Add Entry to DataBase
        String strConnString = System.Configuration.ConfigurationManager.ConnectionStrings["conString"].ConnectionString;
        SqlConnection con = new SqlConnection(strConnString);
        string strQuery = "insert into [Images] (FileName, FilePath) values(@FileName, @FilePath)";
        SqlCommand cmd = new SqlCommand(strQuery);
        cmd.Parameters.AddWithValue("@FileName", FileName);
        cmd.Parameters.AddWithValue("@FilePath", "Files/" + FileName);
        cmd.CommandType = CommandType.Text;
        cmd.Connection = con;
        try
        {
            con.Open();
            cmd.ExecuteNonQuery();
        }
        catch (Exception ex)
        {
            Response.Write(ex.Message);
        }
        finally
        {
            con.Close();
            con.Dispose();
        }
    }
}

public void GenerateThumbNail(string sourcefile, string destinationfile, int width)
{
    if (File.Exists(Server.MapPath(sourcefile)))
    {

        System.Drawing.Image image = System.Drawing.Image.FromFile(Server.MapPath(sourcefile));
        int srcWidth = image.Width;
        int srcHeight = image.Height;
        int thumbWidth = width;
        int thumbHeight;
        Bitmap bmp;
        if (srcHeight > srcWidth)
        {
            thumbHeight = (srcHeight / srcWidth) * thumbWidth;
            bmp = new Bitmap(thumbWidth, thumbHeight);
        }
        else
        {
            thumbHeight = thumbWidth;
            thumbWidth = (srcWidth / srcHeight) * thumbHeight;
            bmp = new Bitmap(thumbWidth, thumbHeight);
        }

        System.Drawing.Graphics gr = System.Drawing.Graphics.FromImage(bmp);
        gr.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
        gr.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality;
        gr.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High;
        System.Drawing.Rectangle rectDestination = new System.Drawing.Rectangle(0, 0, thumbWidth, thumbHeight);
        gr.DrawImage(image, rectDestination, 0, 0, srcWidth, srcHeight, GraphicsUnit.Pixel);

        bmp.Save(Server.MapPath(destinationfile));
        bmp.Dispose();
        image.Dispose();
        DeleteTempImage(sourcefile, destinationfile);

    }
}

private void DeleteTempImage(string sourcefile, string destinationfile)
{
    string directoryPath = Server.MapPath(sourcefile);
    File.Delete(directoryPath);
}

public override void VerifyRenderingInServerForm(Control control)
{
    /* Verifies that the control is rendered */
}

protected void Export_Grid(object sender, EventArgs e)
{
    try
    {
        Response.Clear();
        Response.Buffer = true;
        Response.AddHeader("content-disposition",
            "attachment;filename=EmployeeInfo.xls");
        Response.Charset = "";
        Response.ContentType = "application/vnd.ms-excel";
        StringWriter sw = new StringWriter();
        HtmlTextWriter hw = new HtmlTextWriter(sw);
        gridInformation.AllowPaging = false;
        this.GetImage();
        for (int i = 0; i < gridInformation.Rows.Count; i++)
        {
            GridViewRow row = gridInformation.Rows[i];
            //Apply text style to each Row
            row.Attributes.Add("class", "textmode");
        }
        gridInformation.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();
    }

    catch (Exception)
    {

    }
}

protected string GetUrl(string imagepath)
{
    string[] splits = Request.Url.AbsoluteUri.Split('/');
    if (splits.Length >= 2)
    {
        string url = splits[0] + "//";
        for (int i = 2; i < splits.Length - 1; i++)
        {
            url += splits[i];
            url += "/";
        }
        return url + imagepath;
    }
    return imagepath;
}

protected void gridInformation_RowDataBound(object sender, GridViewRowEventArgs e)
{
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        string imageName = (e.Row.FindControl("lblPath") as Label).Text;
        string[] filename = imageName.Split('/');

        // 70 is define image size.
        GenerateThumbNail("Images/" + filename[1], imageName, 70);
    }
}

VB.Net

    Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
        If Not IsPostBack Then
            Me.GetImage()
        End If
    End Sub

    Private Sub GetImage()
        Dim dt As DataTable = New DataTable()
        Dim strConnString As String = System.Configuration.ConfigurationManager.ConnectionStrings("conString").ConnectionString
        Dim strQuery As String = "select * from [Images]"
        Dim cmd As SqlCommand = New SqlCommand(strQuery)
        Dim con As SqlConnection = New SqlConnection(strConnString)
        Dim sda As SqlDataAdapter = New SqlDataAdapter()
        cmd.CommandType = CommandType.Text
        cmd.Connection = con

        Try
            con.Open()
            sda.SelectCommand = cmd
            sda.Fill(dt)
            gridInformation.DataSource = dt
            gridInformation.DataBind()
        Catch ex As Exception
            Response.Write(ex.Message)
        Finally
            con.Close()
            sda.Dispose()
            con.Dispose()
        End Try
    End Sub

    Protected Sub btnUpload_Click(ByVal sender As Object, ByVal e As EventArgs)
        If FileUpload1.PostedFile IsNot Nothing Then
            Dim FileName As String = Path.GetFileName(FileUpload1.PostedFile.FileName)
            FileUpload1.SaveAs(Server.MapPath("Images/" & FileName))
            Dim strConnString As String = System.Configuration.ConfigurationManager.ConnectionStrings("conString").ConnectionString
            Dim con As SqlConnection = New SqlConnection(strConnString)
            Dim strQuery As String = "insert into [Images] (FileName, FilePath) values(@FileName, @FilePath)"
            Dim cmd As SqlCommand = New SqlCommand(strQuery)
            cmd.Parameters.AddWithValue("@FileName", FileName)
            cmd.Parameters.AddWithValue("@FilePath", "Files/" & FileName)
            cmd.CommandType = CommandType.Text
            cmd.Connection = con

            Try
                con.Open()
                cmd.ExecuteNonQuery()
            Catch ex As Exception
                Response.Write(ex.Message)
            Finally
                con.Close()
                con.Dispose()
            End Try
        End If
    End Sub

    Public Sub GenerateThumbNail(ByVal sourcefile As String, ByVal destinationfile As String, ByVal width As Integer)
        If File.Exists(Server.MapPath(sourcefile)) Then
            Dim image As System.Drawing.Image = System.Drawing.Image.FromFile(Server.MapPath(sourcefile))
            Dim srcWidth As Integer = image.Width
            Dim srcHeight As Integer = image.Height
            Dim thumbWidth As Integer = width
            Dim thumbHeight As Integer
            Dim bmp As Bitmap

            If srcHeight > srcWidth Then
                thumbHeight = (srcHeight / srcWidth) * thumbWidth
                bmp = New Bitmap(thumbWidth, thumbHeight)
            Else
                thumbHeight = thumbWidth
                thumbWidth = (srcWidth / srcHeight) * thumbHeight
                bmp = New Bitmap(thumbWidth, thumbHeight)
            End If

            Dim gr As System.Drawing.Graphics = System.Drawing.Graphics.FromImage(bmp)
            gr.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality
            gr.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality
            gr.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High
            Dim rectDestination As System.Drawing.Rectangle = New System.Drawing.Rectangle(0, 0, thumbWidth, thumbHeight)
            gr.DrawImage(image, rectDestination, 0, 0, srcWidth, srcHeight, GraphicsUnit.Pixel)
            bmp.Save(Server.MapPath(destinationfile))
            bmp.Dispose()
            image.Dispose()
            DeleteTempImage(sourcefile, destinationfile)
        End If
    End Sub

    Private Sub DeleteTempImage(ByVal sourcefile As String, ByVal destinationfile As String)
        Dim directoryPath As String = Server.MapPath(sourcefile)
        File.Delete(directoryPath)
    End Sub

    Public Overrides Sub VerifyRenderingInServerForm(ByVal control As Control)
    End Sub

    Protected Sub Export_Grid(ByVal sender As Object, ByVal e As EventArgs)
        Try
            Response.Clear()
            Response.Buffer = True
            Response.AddHeader("content-disposition", "attachment;filename=EmployeeInfo.xls")
            Response.Charset = ""
            Response.ContentType = "application/vnd.ms-excel"
            Dim sw As StringWriter = New StringWriter()
            Dim hw As HtmlTextWriter = New HtmlTextWriter(sw)
            gridInformation.AllowPaging = False
            Me.GetImage()

            For i As Integer = 0 To gridInformation.Rows.Count - 1
                Dim row As GridViewRow = gridInformation.Rows(i)
                row.Attributes.Add("class", "textmode")
            Next

            gridInformation.RenderControl(hw)
            Dim style As String = "<style> .textmode { mso-number-format:\@; } </style>"
            Response.Write(style)
            Response.Output.Write(sw.ToString())
            Response.Flush()
            Response.End()
        Catch ex As Exception
        End Try
    End Sub

    Protected Function GetUrl(ByVal imagepath As String) As String
        Dim splits As String() = Request.Url.AbsoluteUri.Split("/"c)
        If splits.Length >= 2 Then
            Dim url As String = splits(0) & "//"

            For i As Integer = 2 To splits.Length - 1 - 1
                url += splits(i)
                url += "/"
            Next

            Return url & imagepath
        End If

        Return imagepath
    End Function

    Protected Sub gridInformation_RowDataBound(ByVal sender As Object, ByVal e As GridViewRowEventArgs)
        If e.Row.RowType = DataControlRowType.DataRow Then
            Dim imageName As String = (TryCast(e.Row.FindControl("lblPath"), Label)).Text
            Dim filename As String() = imageName.Split("/"c)
            GenerateThumbNail("Images/" & filename(1), imageName, 70)
        End If
    End Sub

Screenshot