Sorting rows in a data table

Question

We have two columns in a DataTable, like so:

COL1   COL2
Abc    5
Def    8
Ghi    3

We're trying to sort this datatable based on COL2 in decreasing order.

COL1            COL2
ghi             8
abc             4
def             3
jkl             1

We tried this:

ft.DefaultView.Sort = "occr desc";
ft = ft.DefaultView.ToTable(true);

but, without using a DataView, we want to sort the DataTable itself, not the DataView.

Answer 1

It turns out there is a special case where this can be achieved. The trick is when building the DataTable, collect all the rows in a list, sort them, then add them. This case just came up here.

Answer 2

TL;DR

use tableObject.Select(queryExpression, sortOrderExpression) to select data in sorted manner

Complete example

Complete working example - can be tested in a console application:

    using System;
    using System.Data;

    namespace A
    {
        class Program
        {
            static void Main(string[] args)
            {
                DataTable table = new DataTable("Orders");
                table.Columns.Add("OrderID", typeof(Int32));
                table.Columns.Add("OrderQuantity", typeof(Int32));
                table.Columns.Add("CompanyName", typeof(string));
                table.Columns.Add("Date", typeof(DateTime));

                DataRow newRow = table.NewRow();
                newRow["OrderID"] = 1;
                newRow["OrderQuantity"] = 3;
                newRow["CompanyName"] = "NewCompanyName";
                newRow["Date"] = "1979, 1, 31";

                // Add the row to the rows collection.
                table.Rows.Add(newRow);

                DataRow newRow2 = table.NewRow();
                newRow2["OrderID"] = 2;
                newRow2["OrderQuantity"] = 2;
                newRow2["CompanyName"] = "NewCompanyName1";
                table.Rows.Add(newRow2);

                DataRow newRow3 = table.NewRow();
                newRow3["OrderID"] = 3;
                newRow3["OrderQuantity"] = 2;
                newRow3["CompanyName"] = "NewCompanyName2";
                table.Rows.Add(newRow3);

                DataRow[] foundRows;

                Console.WriteLine("Original table's CompanyNames");
                Console.WriteLine("************************************");
                foundRows = table.Select();

                // Print column 0 of each returned row.
                for (int i = 0; i < foundRows.Length; i++)
                    Console.WriteLine(foundRows[i][2]);

                // Presuming the DataTable has a column named Date.
                string expression = "Date = '1/31/1979' or OrderID = 2";
                // string expression = "OrderQuantity = 2 and OrderID = 2";

                // Sort descending by column named CompanyName.
                string sortOrder = "CompanyName ASC";

                Console.WriteLine("\nCompanyNames data for Date = '1/31/1979' or OrderID = 2, sorted CompanyName ASC");
                Console.WriteLine("************************************");
                // Use the Select method to find all rows matching the filter.
                foundRows = table.Select(expression, sortOrder);

                // Print column 0 of each returned row.
                for (int i = 0; i < foundRows.Length; i++)
                    Console.WriteLine(foundRows[i][2]);

                Console.ReadKey();
            }
        }
    }

Output

Answer 3

There is 2 way for sort data

1) sorting just data and fill into grid:

DataGridView datagridview1 = new DataGridView(); // for show data
DataTable dt1 = new DataTable(); // have data
DataTable dt2 = new DataTable(); // temp data table
DataRow[] dra = dt1.Select("", "ID DESC");
if (dra.Length > 0)
    dt2 = dra.CopyToDataTable();
datagridview1.DataSource = dt2;

2) sort default view that is like of sort with grid column header:

DataGridView datagridview1 = new DataGridView(); // for show data
DataTable dt1 = new DataTable(); // have data
dt1.DefaultView.Sort = "ID DESC";
datagridview1.DataSource = dt1;

Answer 4

Did you try using the Select(filterExpression, sortOrder) method on DataTable? See here for an example. Note this method will not sort the data table in place, if that is what you are looking for, but it will return a sorted array of rows without using a data view.

Answer 5

This will help you...

DataTable dt = new DataTable();         
dt.DefaultView.Sort = "Column_name desc";
dt = dt.DefaultView.ToTable();

Answer 6

Its Simple Use .Select function.

DataRow[] foundRows=table.Select("Date = '1/31/1979' or OrderID = 2", "CompanyName ASC");
DataTable dt = foundRows.CopyToDataTable();

And it's done......Happy Coding