Question

我想格式化DataGridView中显示和捕获的小数位，我有一个最小小数位数和最大小数位数。例如：

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)

在DataGridView列中，“txtcDecimal”具有属性（来自设计者）

txtcDecimal.DefaultCellStyle.Format = "N2";

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

掩码“0.00 ##”作为“n2”工作只得到2位小数这是正确的舍入到两个小数位但只是不喜欢我需要的（如我在示例中所示）

如何在不消耗大量资源的情况下以简单的方式完成这项工作？

感谢harlam357＆amp; Tom Garske

Answer 1

要格式化2到4位小数，可以使用自定义格式字符串。

txtcDecimal.DefaultCellStyle.Format = "0.00##"

更进一步......

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

要格式化2到4位小数，可以使用自定义格式字符串。（由Harlam357提供）

txtcDecimal.DefaultCellStyle.Format = "0.00##"

我使用以下简单的控制台应用程序验证了它：

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

输出结果为：

13.10
13.1235

哈拉姆的答案显然是正确的......

更新：这是我在表单中实现它的方式：

    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##");
        }
    }

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

<强>输出：

Example Output from application

Answer 3

创建自定义格式化程序。

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;  
   }  
}

消息来源： How to custom format data in datagridview during databinding

如何在DataGridView中格式化带有max和min的数字十进制的列？

3 个答案: