In this post, I will
explain How to Convert DataTable Rows into Columns (Transpose DataTable) using C# in Asp.Net
application.
To
explain this, I have taken below example. This example uses a DataTable with
four rows and three columns as shown in image 1 and after the button click, it will
call a method GenerateRowsToColumnsTable().
This Method returns
a DataTable with five columns and 2 rows as shown in image 2.
 |
| Image 1 |
 |
| Image 2 |
HTML Code :
<%@
Page Language="C#" AutoEventWireup="true"
CodeBehind="WebForm1.aspx.cs"
Inherits="TestApplication.WebForm1" %>
<!DOCTYPE
html>
<html lang="">
<head
runat="server">
<title>Convert DataTable Rows into
Columns (Transpose DataTable)</title>
</head>
<body>
<form id="form1"
runat="server">
<div>
<table width="60%"
align="center">
<tr>
<td style="
vertical-align: middle; text-align: center;">
<h2>Convert
DataTable From Rows To Columns(Transpose DataTable)</h2>
</td>
</tr>
<tr>
<td style="color: blueviolet;
vertical-align: middle; text-align: left;">
<h3
id="header" runat="server"></h3>
</td>
</tr>
<tr>
<td
width="100%" align="center" valign="top">
<asp:DataGrid
ID="dgView" runat="server"
Width="100%" HorizontalAlign="Center"
CellPadding="4" ForeColor="#333333"
GridLines="Both">
<AlternatingItemStyle BackColor="White" />
<FooterStyle
BackColor="#990000" Font-Bold="True" ForeColor="White"
/>
<HeaderStyle
BackColor="#990000" Font-Bold="True"
ForeColor="White" />
<ItemStyle BackColor="#FFFBD6"
ForeColor="#333333" />
<PagerStyle
BackColor="#FFCC66" ForeColor="#333333"
HorizontalAlign="Center" />
<SelectedItemStyle BackColor="#FFCC66"
Font-Bold="True" ForeColor="Navy" />
</asp:DataGrid>
</td>
</tr>
<tr>
<td> </td>
</tr>
<tr>
<td
align="center">
<asp:Button
ID="btnRowsToColumns" runat="server" Text="Convert
Rows To Columns" OnClick="btnRowsToColumns_Click" />
</td>
</tr>
</table>
</div>
</form>
</body>
</html>
C# Code :
using
System;
using
System.Collections.Generic;
using
System.Data;
using
System.Linq;
using
System.Web;
using
System.Web.UI;
using
System.Web.UI.WebControls;
namespace
TestApplication
{
public partial class WebForm1 :
System.Web.UI.Page
{
protected void Page_Load(object sender,
EventArgs e)
{
if (!IsPostBack)
{
header.InnerText = "Data
Table before Transpose :";
BindGrid(CreateDataTable());
}
}
protected void
btnRowsToColumns_Click(object sender, EventArgs e)
{
header.InnerText = "Data Table
after Transpose :";
DataTable MainTable =
CreateDataTable(); // Table in Figure 1
BindGrid(GenerateRowsToColumnsTable(MainTable));
btnRowsToColumns.Visible = false;
}
private void BindGrid(DataTable tbl)
{
dgView.DataSource = tbl;
dgView.DataBind();
}
private DataTable CreateDataTable()
{
DataTable tbl = new DataTable();
tbl.Columns.Add("Column1", typeof(string));
tbl.Columns.Add("Column2", typeof(string));
tbl.Columns.Add("Column3", typeof(string));
tbl.Rows.Add("Row1",
"RC12", "RC13");
tbl.Rows.Add("Row2",
"RC22", "RC23");
tbl.Rows.Add("Row3",
"RC32", "RC33");
tbl.Rows.Add("Row4",
"RC42", "RC43");
return tbl;
}
private DataTable
GenerateRowsToColumnsTable(DataTable MainTable)
{
DataTable OutputTable = new
DataTable();
// Add columns by looping rows
// Header row's first column is
same as in MainTable
OutputTable.Columns.Add(MainTable.Columns[0].ColumnName.ToString());
// Header row's second column
onwards, 'MainTable's first column taken
foreach (DataRow inRow in
MainTable.Rows)
{
string newColName =
inRow[0].ToString();
OutputTable.Columns.Add(newColName);
}
// Add rows by looping columns
for (int rCount = 1; rCount <=
MainTable.Columns.Count - 1; rCount++)
{
DataRow newRow =
OutputTable.NewRow();
// First column is MainTable's
Header row's second column
newRow[0] =
MainTable.Columns[rCount].ColumnName.ToString();
for (int cCount = 0; cCount
<= MainTable.Rows.Count - 1; cCount++)
{
string colValue =
MainTable.Rows[cCount][rCount].ToString();
newRow[cCount + 1] =
colValue;
}
OutputTable.Rows.Add(newRow);
}
return OutputTable;
}
}
}