Merge column of multiple rows into one using C# and VB.Net in ASP.Net

Hi dorsa,

Use DataList control and set RepeatColumns according to your need.

To hide ShowChart Button for .sim file check the condition and set visible property.

Refer below code.

HTML

<asp:DataList ID="DataList1" runat="server" RepeatLayout="Table" RepeatColumns="2">
    <ItemTemplate>
        <table>
        <tr>
            <td><%# Eval("Text") %></td>
            <td><asp:LinkButton ID="lnkDownload" Text="Download" CommandArgument='<%# Eval("Value") %>' runat="server" OnClick="DownloadFile"></asp:LinkButton></td>
            <td><asp:LinkButton ID="lnkShowChrt" Text="ShowCharts" CommandArgument='<%# Eval("Value") %>' runat="server" /></td>
        </tr>
        </table>
    </ItemTemplate>
</asp:DataList>

Code

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
        string[] filePaths = System.IO.Directory.GetFiles(Server.MapPath("~/Admin/ExResults/"), "Results_123." + "*");
        string[] filePaths1 = System.IO.Directory.GetFiles(Server.MapPath("~/Admin/ExResults/"), "FinalModel_123." + "*");

        List<ListItem> Xlsxfiles = new List<ListItem>();
        foreach (string filePath in filePaths)
        {
            Xlsxfiles.Add(new ListItem(System.IO.Path.GetFileName(filePath), filePath));
        }
        List<ListItem> Simfiles = new List<ListItem>();
        foreach (string filePath in filePaths1)
        {
            Simfiles.Add(new ListItem(System.IO.Path.GetFileName(filePath), filePath));
        }

        var Files = Xlsxfiles.Concat(Simfiles);
        DataList1.DataSource = Files;
        DataList1.DataBind();
    }
}
protected void DownloadFile(object sender, EventArgs e)
{
    string filePath = ((LinkButton)sender).CommandArgument;
    Response.ContentType = ContentType;
    Response.AppendHeader("Content-Disposition", "attachment; filename=" + System.IO.Path.GetFileName(filePath));
    Response.WriteFile(filePath);
    Response.End();
}
protected void DataList1_ItemDataBound(object sender, DataListItemEventArgs e)
{
    if (e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem)
    {
        LinkButton lnk = e.Item.FindControl("lnkShowChrt") as LinkButton;
        if (lnk.CommandArgument.EndsWith(".sim"))
        {
            lnk.Visible = false;
        }
    }
}

VB.Net

Protected Sub Page_Load(sender As Object, e As EventArgs) Handles Me.Load
    If Not IsPostBack Then
        Dim filePaths As String() = Directory.GetFiles(Server.MapPath("~/Admin/ExResults/"), "Results_123." + "*")
        Dim filePaths1 As String() = Directory.GetFiles(Server.MapPath("~/Admin/ExResults/"), "FinalModel_123." + "*")

        Dim Xlsxfiles As List(Of ListItem) = New List(Of ListItem)()
        For Each filePath As String In filePaths
            Xlsxfiles.Add(New ListItem(System.IO.Path.GetFileName(filePath), filePath))
        Next
        Dim Simfiles As List(Of ListItem) = New List(Of ListItem)()
        For Each filePath As String In filePaths1
            Simfiles.Add(New ListItem(System.IO.Path.GetFileName(filePath), filePath))
        Next

        Dim Files = Xlsxfiles.Concat(Simfiles)
        DataList1.DataSource = Files
        DataList1.DataBind()
    End If
End Sub
Protected Sub DownloadFile(ByVal sender As Object, ByVal e As EventArgs)
    Dim filePath As String = CType(sender, LinkButton).CommandArgument
    Response.ContentType = ContentType
    Response.AppendHeader("Content-Disposition", ("attachment; filename=" + Path.GetFileName(filePath)))
    Response.WriteFile(filePath)
    Response.End()
End Sub
Protected Sub DataList1_ItemDataBound(sender As Object, e As DataListItemEventArgs)
    If e.Item.ItemType = ListItemType.Item OrElse e.Item.ItemType = ListItemType.AlternatingItem Then
        Dim lnk As LinkButton = e.Item.FindControl("lnkShowChrt")
        If lnk.CommandArgument.EndsWith(".sim") Then
            lnk.Visible = False
        End If
    End If
End Sub

Screenshot