ASP.NET Tutorial/ADO.net Database/CSV

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Create connection to csv text based database (C#)

   <source lang="csharp">

<%@ Page Language="C#" %> <%@ import Namespace="System.Data" %> <%@ import Namespace="System.Data.OleDb" %> <script runat="server">

   void Page_Load(object sender, EventArgs e) {
   
       string ConnectionString = @"Provider=Microsoft.Jet.OLEDB.4.0; Data Source=C:\Database; Extended Properties=""text;HDR=YES;"";";
       string CommandText = "select * from csv.txt";
   
       OleDbConnection myConnection = new OleDbConnection(ConnectionString);
       OleDbCommand myCommand = new OleDbCommand(CommandText, myConnection);
   
       myConnection.Open();
   
       DataGrid1.DataSource = myCommand.ExecuteReader(CommandBehavior.CloseConnection);
       DataGrid1.DataBind();
   
       myConnection.Close();
   }

</script> <html> <head> </head> <body>

   <form runat="server">
       <asp:datagrid id="DataGrid1" runat="server" EnableViewState="False" ForeColor="Black" BackColor="White" CellPadding="3" GridLines="None" CellSpacing="1">
           <HeaderStyle font-bold="True" forecolor="white" backcolor="#4A3C8C"></HeaderStyle>
           <ItemStyle backcolor="#DEDFDE"></ItemStyle>
       </asp:datagrid>
   </form>

</body> </html></source>


Load csv file to DataTable (C#)

   <source lang="csharp">

<%@ Page Language="C#" Debug="true" %> <script runat="server"> private void Page_Load(object sender, System.EventArgs e) {

 if(!IsPostBack)
 {
   string MyFileName;
   System.IO.StreamReader ObjectStreamReader = null;
   System.Data.DataTable ColorTable = new System.Data.DataTable("colors");
   String[] fileRow;
   System.Data.DataColumn dc;
   System.Data.DataRow dr;
   dc = new System.Data.DataColumn("Hex",typeof(string));
   ColorTable.Columns.Add(dc);
   dc = new System.Data.DataColumn("String",typeof(string));
   ColorTable.Columns.Add(dc);
   MyFileName = Page.MapPath("Data.csv");
   try 
   {
     ObjectStreamReader = new System.IO.StreamReader (MyFileName);
     while (ObjectStreamReader.Peek() > -1) {
       dr = ColorTable.NewRow();
       fileRow = ObjectStreamReader.ReadLine().Split(",");
       dr[0] = fileRow[0];
       dr[1] = fileRow[1];
       ColorTable.Rows.Add(dr);
     }
     Label1.Text = "Select a color:";    
     DropDownList1.DataSource = ColorTable;
     DropDownList1.DataTextField = "String";
     DropDownList1.DataValueField = "Hex";
     DropDownList1.DataBind();
   } 
   catch (Exception ObjectError) 
   {
     Label1.Text = ObjectError.Message;
     DropDownList1.Visible = false;
   } 
   finally 
   {
     if (ObjectStreamReader != null) 
     {
       ObjectStreamReader.Close();
     }
   }
 }  

} </script> <html>

 <head>
 </head>
 <body>
   <form runat="server">
     <asp:Label id="Label1" runat="server"></asp:Label>
     <asp:DropDownList id="DropDownList1" runat="server"></asp:DropDownList>
   </form>
 </body>

</html></source>


Load csv file to DataTable (VB)

   <source lang="csharp">

<%@ Page Language="VB" Debug="true" %> <script runat="server"> Sub Page_Load (Sender As Object, E As EventArgs)

 If Not IsPostBack Then
   Dim MyFileName as String
   Dim ObjectStreamReader as System.IO.StreamReader
   Dim ColorTable As New System.Data.DataTable("Colors")
   Dim fileRow() As String
   Dim dc As System.Data.DataColumn
   Dim dr As System.Data.DataRow
   dc = new System.Data.DataColumn("Hex",GetType(String))
   ColorTable.Columns.Add(dc)
   dc = new System.Data.DataColumn("String",GetType(String))
   ColorTable.Columns.Add(dc)
   MyFileName = Page.MapPath("Data.csv")
   Try
     ObjectStreamReader = new System.IO.StreamReader (MyFileName)
     While ObjectStreamReader.Peek() > -1
       dr = ColorTable.NewRow()
       fileRow = ObjectStreamReader.ReadLine().Split(",")
       dr(0) = fileRow(0)
       dr(1) = fileRow(1)
       ColorTable.Rows.Add(dr)
     End While
     Label1.Text = "Select a color:"    
     DropDownList1.DataSource = ColorTable
     DropDownList1.DataTextField = "String"
     DropDownList1.DataValueField = "Hex"
     DropDownList1.DataBind()
   Catch ObjectError as Exception
     Label1.Text = ObjectError.Message
     DropDownList1.Visible = False
   Finally
     If Not ObjectStreamReader Is nothing Then
       ObjectStreamReader.Close()
     End If
   End Try
 End If

End Sub </script> <html>

 <head>
 </head>
 <body>
   <form runat="server">
     <asp:Label id="Label1" runat="server"></asp:Label>
     <asp:DropDownList id="DropDownList1" runat="server"></asp:DropDownList>
   </form>
 </body>

</html></source>