[Solved] ClosedXML Error: Latebound overload resolution cannot be applied to Cell because the accessing instance in an interface app

Hi farahlawi95,

Check this example. Now please take its reference and correct your code.

HTML

<asp:Button ID="btnExport" runat="server" Text="Export To Excel" OnClick="ExportExcel" />

Namespaces

C#

using System.Data;
using System.IO;
using ClosedXML.Excel;

VB.Net

Imports System.Data
Imports System.IO
Imports ClosedXML.Excel

Code

C#

protected void ExportExcel(object sender, EventArgs e)
{
    DataTable dt = Data();
    using (XLWorkbook wb = new XLWorkbook())
    {
        wb.Worksheets.Add(dt, "Data");
        wb.Worksheet("Data").ColumnWidth = 30;
        wb.Worksheet("Data").RowHeight = 20;

        foreach (var row in wb.Worksheet("Data").RowsUsed())
        {
            foreach (var cell in row.CellsUsed())
            {
                if (cell.GetValue<string>().ToString().ToUpper() == "VALID")
                {
                    // Changing color to Green.
                    cell.Style.Fill.BackgroundColor = XLColor.Green;
                }
                if (cell.GetValue<string>().ToString().ToUpper() == "NOTDONE")
                {
                    // Changing color to Red.
                    cell.Style.Fill.BackgroundColor = XLColor.Red;
                }
            }

        }
        wb.Worksheet("Data").Columns().AdjustToContents();
        wb.Worksheet("Data").Table("Table1").ShowAutoFilter = false;
        wb.Worksheet("Data").Table("Table1").Theme = XLTableTheme.None;
        Response.Clear();
        Response.Buffer = true;
        Response.Charset = "";
        Response.ContentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
        Response.AddHeader("content-disposition", "attachment;filename=Test.xlsx");
        using (MemoryStream MyMemoryStream = new MemoryStream())
        {
            wb.SaveAs(MyMemoryStream);
            MyMemoryStream.WriteTo(Response.OutputStream);
            Response.Flush();
            Response.End();
        }
    }
}

private DataTable Data()
{
    DataTable dt = new DataTable();
    dt.Columns.AddRange(new DataColumn[] {
        new DataColumn("Col1"),
        new DataColumn("Col2"),
        new DataColumn("Col3") });
    dt.Rows.Add("VALID", "Java", "NOTDONE");
    dt.Rows.Add("NOTDONE", "ASP.Net", "VALID");
    dt.Rows.Add("0003", "SQL", "VALID");
    dt.Rows.Add("NOTDONE", "jQuery", "NOTDONE");
    return dt;
}

VB.Net

Protected Sub ExportExcel(ByVal sender As Object, ByVal e As EventArgs)
    Dim dt As DataTable = Data()
    Using wb As XLWorkbook = New XLWorkbook()
        wb.Worksheets.Add(dt, "Data")
        wb.Worksheet("Data").ColumnWidth = 30
        wb.Worksheet("Data").RowHeight = 20
        For Each row In wb.Worksheet("Data").RowsUsed()
            For Each cell In row.CellsUsed()
                ' Changing color to Green.
                If cell.GetValue(Of String)().ToString().ToUpper() = "VALID" Then
                    cell.Style.Fill.BackgroundColor = XLColor.Green
                End If
                ' Changing color to Red.
                If cell.GetValue(Of String)().ToString().ToUpper() = "NOTDONE" Then
                    cell.Style.Fill.BackgroundColor = XLColor.Red
                End If
            Next
        Next

        wb.Worksheet("Data").Columns().AdjustToContents()
        wb.Worksheet("Data").Table("Table1").ShowAutoFilter = False
        wb.Worksheet("Data").Table("Table1").Theme = XLTableTheme.None
        Response.Clear()
        Response.Buffer = True
        Response.Charset = ""
        Response.ContentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"
        Response.AddHeader("content-disposition", "attachment;filename=Test.xlsx")
        Using MyMemoryStream As MemoryStream = New MemoryStream()
            wb.SaveAs(MyMemoryStream)
            MyMemoryStream.WriteTo(Response.OutputStream)
            Response.Flush()
            Response.End()
        End Using
    End Using
End Sub

Private Function Data() As DataTable
    Dim dt As DataTable = New DataTable()
    dt.Columns.AddRange(New DataColumn() {
                        New DataColumn("Col1"),
                        New DataColumn("Col2"),
                        New DataColumn("Col3")})
    dt.Rows.Add("VALID", "Java", "NOTDONE")
    dt.Rows.Add("NOTDONE", "ASP.Net", "VALID")
    dt.Rows.Add("0003", "SQL", "VALID")
    dt.Rows.Add("NOTDONE", "jQuery", "NOTDONE")
    Return dt
End Function

Screenshot