Question

如何在System.Windows.Forms.DataGrid中设置包含double，float或decimal数字的数据列的精度？

对于DataGridView，例如有How to format a column with number decimal with max and min in DataGridView?。

我希望0.0100000001显示为0.01，例如，小数点后的2位精度。我想避免它们看起来像这样，浮动和双重使用科学记数法：

我用来填表的代码是：

var table = new DataTable();
table.Columns.Add("double");
table.Columns.Add("float");
table.Columns.Add("decimal");
table.Columns[0].DataType = typeof(double);
table.Columns[1].DataType = typeof(float);
table.Columns[2].DataType = typeof(decimal);
table.Rows.Add(new object[] { 0.00000000000423, 0.00000000000423, 0.00000000000423 });
dataGrid1.DataSource = table;

注意：我知道DataGrid已经过时，但是我处理遗留代码，请不要发表评论告诉我使用DataGridView - 它对我没有帮助。

Answer 1

我从@stuartd评论中获得了我的解决方案。我需要为DataGrid设置Format列of the current table style。

/// <summary>
///  Getting and setting the column widths of a DataGrid is not easy at all.
///  This helper class handles it, including saving and restoring from a string.
/// </summary>
static class DataGridColumnWidthExtensions
{
    /// Get the current table style.
    public static DataGridTableStyle GetCurrentTableStyle(this DataGrid grid)
    {
        // DataGrid holds the current grid table style into a private field called myGridTable.
        // The field points to the "default" table style even if TableStyles is empty. The 
        // default table style is also private/internal.
        // See https://stackoverflow.com/a/39832554/492336 and 
        // https://referencesource.microsoft.com/#System.Windows.Forms/winforms/Managed/System/WinForms/DataGrid.cs,211.
        FieldInfo[] fields = grid.GetType().GetFields(
                     BindingFlags.NonPublic |
                     BindingFlags.Instance);

        return (DataGridTableStyle)fields.First(item => item.Name == "myGridTable").GetValue(grid);
    }
}

然后我们可以迭代GridColumnStyles并为每个数字列设置Format属性：

var tableStyle = dataGrid1.GetCurrentTableStyle();
for (int ii = 0; ii < table.Columns.Count; ii++)
{
    var columnStyle = tableStyle.GridColumnStyles[ii] as DataGridTextBoxColumn;
    if (columnStyle == null)
    {
        // DataGridTextBoxColumn inherits DataGridColumnStyle but in theory
        // a column might be of some other type deriving from DataGridColumnStyle.
        continue;
    }

    var columnType = table.Columns[ii].DataType;
    if (columnType != typeof(double) && columnType != typeof(float) && columnType != typeof(decimal))
    {
        // We set the format only for numeric columns.
        continue;
    }

    // 2 digits after the decimal mark.
    columnStyle.Format = "N2";
}

Answer 2

请找到更新的ans

function RedirectPage(path)
{


  var intWidth = screen.width - 10; //Adjust for the end of screen    var intHeight = screen.height - 80; //Adjust for the Icon Bar at the bottom of the window.
  var strWinProp = " toolbar=no"         //Back, Forward, etc...
               + ",location=no"      //URL field
               + ",directories=no"   //"What's New", etc...
               + ",status=yes"       //Status Bar at bottom of window.
               + ",menubar=no"       //Menubar at top of window.
               + ",resizable=yes"     //Allow resizing by dragging.
               + ",scrollbars=yes"   //Displays scrollbars is document is larger than window.
               + ",titlebar=yes"     //Enable/Disable titlebar resize capability.
               + ",width="+intWidth    //Standard 640,800/788, 800/788
               + ",height="+intHeight  //Standard 480,600/541, 600/566               
               + ",top=0"              //Offset of windows top edge from screen.
               + ",left=0"             //Offset of windows left edge from screen.
               + "";  
    var win = window.open(path,'_blank',strWinProp);
    window.location.href ="closer.html";

始终首先绑定datagrid，然后格式化列

在System.Windows.Forms.DataGrid中设置double / float / decimal的精度

2 个答案: