Delete file from folder on GridView RowDeleting event using C# and VB.Net in ASP.Net

Hi yati,

I have created sample code which full-fill your requirement.

HTML

<form id="form1" runat="server">
<div>
    <div>
        <b><u>LIST OF FILE</u></b><br />
        <br />
    </div>
    <asp:GridView ID="GridViewDocument" runat="server" AutoGenerateColumns="False" AllowPaging="True"
        AllowSorting="True" DataKeyNames="Id" OnRowDeleting="GridViewDocument_RowDeleting"
        CssClass="GridViewStyle" PageSize="5" Width="30%" ShowHeaderWhenEmpty="true"
        EmptyDataText="No Records Found" EmptyDataRowStyle-HorizontalAlign="Center" EmptyDataRowStyle-Height="33">
        <Columns>
            <asp:TemplateField HeaderText="No">
                <ItemStyle Width="5%" VerticalAlign="Middle" HorizontalAlign="center" />
                <ItemTemplate>
                    <%# Container.DataItemIndex + 1 %><asp:Label ID="lblStudentID" runat="server" Text='<%#Bind("Id") %>'
                        Visible="false"></asp:Label></ItemTemplate>
            </asp:TemplateField>
            <asp:TemplateField HeaderText="File" Visible="True">
                <ItemStyle Width="30%" VerticalAlign="Middle" HorizontalAlign="left" />
                <ItemTemplate>
                    <asp:Label ID="lblFilename" runat="server" Text='<%#Bind("FileName")%>'></asp:Label>
                </ItemTemplate>
            </asp:TemplateField>
            <asp:TemplateField HeaderText="Delete" ItemStyle-HorizontalAlign="Center" ItemStyle-Width="10%">
                <ItemTemplate>
                    <asp:LinkButton ID="btnDelete" runat="server" CommandName="Delete" Text="Delete"
                        EnableViewState="false" OnClientClick="return confirm('Are you sure you want to delete?');">
                    </asp:LinkButton>
                </ItemTemplate>
            </asp:TemplateField>
        </Columns>
        <PagerSettings FirstPageText="First" LastPageText="Last" Mode="NumericFirstLast" />
        <RowStyle CssClass="RowStyle" />
        <EmptyDataRowStyle CssClass="EmptyRowStyle" />
        <PagerStyle CssClass="PagerStyle" />
        <SelectedRowStyle CssClass="SelectedRowStyle" />
        <HeaderStyle CssClass="HeaderStyle" HorizontalAlign="Center" />
        <EditRowStyle CssClass="EditRowStyle" />
    </asp:GridView>
</div>
<asp:Label ID="lblmsgStudent" Text="" runat="server" />
</form>

C#

private string Config = ConfigurationManager.ConnectionStrings["constr"].ToString();
protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
        this.GetData();
    }
}

private void GetData()
{
    DataTable dt = new DataTable();
    SqlConnection con = new SqlConnection(Config);
    SqlCommand cmd = new SqlCommand("SELECT * FROM [File]", con);
    SqlDataAdapter sda = new SqlDataAdapter(cmd);
    sda.Fill(dt);
    GridViewDocument.DataSource = dt;
    GridViewDocument.DataBind();
}

protected void GridViewDocument_RowDeleting(Object sender, GridViewDeleteEventArgs e)
{
    string Id = GridViewDocument.DataKeys[e.RowIndex].Value.ToString();
    string FileName = (GridViewDocument.Rows[e.RowIndex].FindControl("lblFilename") as Label).Text;
    SqlConnection con = new SqlConnection(Config);
    SqlCommand cmdDocument = new SqlCommand("delete from [File] where Id=" + Id, con);
    con.Open();
    cmdDocument.ExecuteNonQuery();
    con.Close();
    DeleteFile(FileName);
    lblmsgStudent.Text = "document successfully deleted.";
    this.GetData();
}

private void DeleteFile(string FileName)
{
    foreach (string file in System.IO.Directory.GetFiles("D:\\Users\\Indresh\\TestFolder"))
    {
        if (System.IO.File.Exists(file))
        {
            if (file.CompareTo("D:\\Users\\Indresh\\TestFolder\\" + FileName).ToString() == "0")
            {
                System.IO.File.Delete(file);
            }
        }
    }
}

Vb.Net

Private Config As String = ConfigurationManager.ConnectionStrings("constr").ToString()
Protected Sub Page_Load(sender As Object, e As EventArgs)
	If Not IsPostBack Then
		Me.GetData()
	End If
End Sub

Private Sub GetData()
	Dim dt As New DataTable()
	Dim con As New SqlConnection(Config)
	Dim cmd As New SqlCommand("SELECT * FROM [File]", con)
	Dim sda As New SqlDataAdapter(cmd)
	sda.Fill(dt)
	GridViewDocument.DataSource = dt
	GridViewDocument.DataBind()
End Sub

Protected Sub GridViewDocument_RowDeleting(sender As [Object], e As GridViewDeleteEventArgs)
	Dim Id As String = GridViewDocument.DataKeys(e.RowIndex).Value.ToString()
	Dim FileName As String = TryCast(GridViewDocument.Rows(e.RowIndex).FindControl("lblFilename"), Label).Text
	Dim con As New SqlConnection(Config)
	Dim cmdDocument As New SqlCommand(Convert.ToString("delete from [File] where Id=") & Id, con)
	con.Open()
	cmdDocument.ExecuteNonQuery()
	con.Close()
	DeleteFile(FileName)
	lblmsgStudent.Text = "document successfully deleted."
	Me.GetData()
End Sub

Private Sub DeleteFile(FileName As String)
	For Each file As String In System.IO.Directory.GetFiles("D:\Users\Indresh\TestFolder")
		If System.IO.File.Exists(file) Then
			If file.CompareTo(Convert.ToString("D:\Users\Indresh\TestFolder\") & FileName).ToString() = "0" Then
				System.IO.File.Delete(file)
			End If
		End If
	Next
End Sub

Screenshot

yati says:

SqlCommand cmd = new SqlCommand("SELECT * from StudentDocument where StudentID=" + StudentID, con);

 Replace above code with below.

 SqlCommand cmd = new SqlCommand("SELECT * from StudentDocument where StudentID='" + StudentID.Value + "'", con);