How to format a column with the number of decimal numbers with max and min in a DataGridView?

Question

I want to format the decimal places displayed and captured in a DataGridView, I have a minimum number of decimal places and a maximum number of decimal places. For example:

If caught, "120.0" display "120.00" If caught "120.01" display "120.01" If caught "120,123" display "120,123" If caught "120.1234" display "120.1234" If caught "120.12348" display "120.1235" (round) 

In the DataGridView column, "txtcDecimal" has a property (from the designer)

 txtcDecimal.DefaultCellStyle.Format = "N2"; txtcDecimal.DefaultCellStyle.Format = "0.00##"; // IS ANSWER. I do not work for an event that interfered 

The mask "0,00 ##" works like "n2", it only gets 2 decimal places which does the right rounding to two decimal places, but just don’t like what I need (as shown in the example)

How can I do this in a simple way without consuming a lot of resources?

Thanks harlam357 and Tom Garske

Answer 1

You can use a custom format string to format 2 to 4 decimal places.

 txtcDecimal.DefaultCellStyle.Format = "0.00##" 

To go a little further ...

 public partial class Form1 { public Form1() { InitializeComponent(); var list = new List<Data>(); list.Add(new Data { Prop1 = 1, Prop2 = 1.2 }); list.Add(new Data { Prop1 = 2, Prop2 = 1.234567 }); dataGridView1.Columns.Add("Prop1", "Prop1"); dataGridView1.Columns["Prop1"].DataPropertyName = "Prop1"; dataGridView1.Columns.Add("Prop2", "Prop2"); dataGridView1.Columns["Prop2"].DataPropertyName = "Prop2"; dataGridView1.Columns["Prop2"].DefaultCellStyle.Format = "0.00##"; dataGridView1.DataSource = list; } class Data { public int Prop1 { get; set; } public double Prop2 { get; set; } } } 

Answer 2

You can use a custom format string to format 2 to 4 decimal places. (As provided by Harlam357)

 txtcDecimal.DefaultCellStyle.Format = "0.00##" 

I tested it with the following simple console application:

  double myDouble = 13.1; double myDouble2 = 13.12345; Console.WriteLine(myDouble.ToString("0.00##")); Console.WriteLine(myDouble2.ToString("0.00##")); Console.Read(); 

The output was:

 13.10 13.1235 

Harlam's answer is clearly correct ....

UPDATE: Here's how I implemented it in forms:

  public Form1() { InitializeComponent(); DataTable dt = new DataTable(); dt.Columns.Add("a"); dt.Rows.Add(123.4); dt.Rows.Add(123.45); dt.Rows.Add(123.456); dt.Rows.Add(123.4567); dt.Rows.Add(123.45678); this.dataGridView1.DataSource = dt; this.dataGridView1.CellFormatting += new DataGridViewCellFormattingEventHandler(dataGridView1_CellFormatting); } void dataGridView1_CellFormatting(object sender, DataGridViewCellFormattingEventArgs e) { if (e.ColumnIndex == 0 && e.RowIndex != this.dataGridView1.NewRowIndex) { double d = double.Parse(e.Value.ToString()); e.Value = d.ToString("0.00##"); } } 

SOURCE: http://social.msdn.microsoft.com/forums/en-US/winformsdatacontrols/thread/95e7e7ef-2e71-412f-abe5-ffbee2c12c18/

OUTPUT:

Answer 3

Create a custom formatter.

 public class MyFormatProvider : IFormatProvider, ICustomFormatter { public object GetFormat(Type formatType) { if (formatType == typeof(ICustomFormatter)) return this; else return null; } public string Format(string format, object arg, IFormatProvider formatProvider) { // Check whether this is an appropriate callback if (!this.Equals(formatProvider)) return null; //if argument/ value is null we return empty string if (arg == null) return null; string resultString = arg.ToString(); //transform resultString any way you want (could do operations based on given format parameter) //return the resultant string return resultString; } } 

SOURCE: As user-format data in a datagridview during data binding