c# how to correctly align number in DataGrid

Question

I have a working Windows Forms application that loads in transaction-data and categorizes it, adding the amount of euros spent on that certain category.

The amount of euros is shown in the dataTable as follows:

but I want the correct alignment when it comes to representing numbers. So this is what I mean:

Now I know a devious way to dealing with this problem (since: how should a dataTable-object itself know how to align to my wishes?)

But I would like to know if there is a better approach for this situation.

Answer 1

I'm assuming it's Windows Forms application.

Below is a sample app with a DataGrid with 2 columns, one of which has its values right-aligned. The essential line here is

Alignment = HorizontalAlignment.Right

The app (copy/paste and run it to see the result):

using System.Data;
using System.Drawing;
using System.Windows.Forms;

public class Form1 : System.Windows.Forms.Form
{
    public static void Main()
    {
        Application.Run(new Form1());
    }

    public Form1()
    {
        var myDataGrid = new DataGrid();
        ClientSize = new System.Drawing.Size(450, 330);
        myDataGrid.Location = new Point(24, 50);
        myDataGrid.Size = new Size(300, 200);

        Controls.Add(myDataGrid);

        myDataGrid.SetDataBinding(MakeDataSet(), "MyTable");

        var tableStyle = new DataGridTableStyle { MappingName = "MyTable" };
        var nameColumnStyle = new DataGridTextBoxColumn { MappingName = "Name" };
        var sumColumnStyle = new DataGridTextBoxColumn
        {
            MappingName = "Sum",
            Width = 170,
            Alignment = HorizontalAlignment.Right
        };
        tableStyle.GridColumnStyles.Add(nameColumnStyle);
        tableStyle.GridColumnStyles.Add(sumColumnStyle);
        myDataGrid.TableStyles.Add(tableStyle);
    }

    private DataSet MakeDataSet()
    {
        var dataSet = new DataSet("myDataSet");
        var table = new DataTable("MyTable");
        var nameCol = new DataColumn("Name");
        var sumCol = new DataColumn("Sum", typeof(float));
        table.Columns.Add(nameCol);
        table.Columns.Add(sumCol);

        dataSet.Tables.Add(table);

        var row1 = table.NewRow();
        row1["Name"] = "Bank";
        row1["Sum"] = 1.25;
        table.Rows.Add(row1);

        var row2 = table.NewRow();
        row2["Name"] = "Hosting";
        row2["Sum"] = 12.5;
        table.Rows.Add(row2);

        return dataSet;
    }
}

UPDATE

Here's an example of the custom alignment you need, it's a console app but the same code will work in a Windows Forms app:

    class Program
    {
        static void Main(string[] args)
        {
            var numbers = new[] { 1, 100.12, 50.218, 0.5 };
            int length = 10;
            var separator = CultureInfo.CurrentCulture.NumberFormat.NumberDecimalSeparator;

            foreach (var n in numbers.Select(i => i.ToString()))
            {
                var offset = n.Contains(separator) ? n.Length - n.IndexOf(separator) : 0;
                string format = string.Format("{{0, {0}}}", length + offset);
                Console.WriteLine(string.Format(format, n));
            }
        }
    }

Tweak the variable length to your needs.