如何按列名更改gridview单元格前景？

Question

我有一个像这样的Gridview：

我需要检查最后一列日期，如果比今天更早，则更改前景色。

我试过这样：

DateTime dt;
string today = DateTime.Now.ToString("dd.MM.yyyy");
int lastcol = e.Row.Cells.Count - 1;
if (DateTime.TryParseExact(e.Row.Cells[lastcol].Text, "dd.MM.yyyy", CultureInfo.InvariantCulture, DateTimeStyles.None, out dt))
{
    string dtstr = dt.ToString("dd.MM.yyyy");
    if (dtstr != today)
    {
         e.Row.Cells[lastcol].ForeColor = System.Drawing.Color.Red;
    }
}

它正在为这样的列名工作（我知道因为DateTime Tryparse ......）：

我需要更改最后一列的每个单元格的前景色（如果比今天更早）：

我该怎么做？

Answer 1

这没效果？

DateTime dt;
GridView myGrid = new GridView();
GridViewRow e = myGrid.SelectRow(0);
int lastcol = e.Row.Cells.Count - 1;
if (DateTime.TryParseExact(e.Row.Cells[lastcol].Text, "dd.MM.yyyy", CultureInfo.InvariantCulture, DateTimeStyles.None, out dt))
{
    if (dt > DateTime.Now)
    {
         for each(GridViewRow current in myGrid.Rows)
         {                 
             current.Cells[lastcol].ForeColor = System.Drawing.Color.Red;
         }
    }
}

Answer 2

好吧，如果你做了一个会做事情的foreach：

Well if you make a foreach that will do the thing :

DateTime dt;
string today = DateTime.Now.ToString("dd.MM.yyyy");
int lastcol = e.Row.Cells.Count - 1;
if (DateTime.TryParseExact(e.Row.Cells[lastcol].Text, "dd.MM.yyyy", CultureInfo.InvariantCulture, DateTimeStyles.None, out dt))
{
    string dtstr = dt.ToString("dd.MM.yyyy");
    if (dtstr != today)
    {
         foreach (Gridview a in idGridView.Rows)
    {
     a.Cells[7].ForeColor = System.Drawing.Color.Red
    }   
 }
}

Answer 3

尝试在RowDataBound事件中创建

   protected void GridView_RowDataBound(object sender, GridViewRowEventArgs e)
{
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        e.Row.Cells[GetColumnIndexByName(e.Row, "yourDate")].ForeColor  = System.Drawing.Color.Red ;
    }
}

使用此halper方法

int GetColumnIndexByName(GridViewRow row, string SearchColumnName)
        {
            int columnIndex = 0;
            foreach (DataControlFieldCell cell in row.Cells)
            {
                if (cell.ContainingField is BoundField)
                {
                    if (((BoundField)cell.ContainingField).DataField.Equals(SearchColumnName))
                    {
                        break;
                    }
                }
                columnIndex++;
            }
            return columnIndex;
        }

Answer 4

这样做。

if (DateTime.TryParseExact(e.Row.Cells[lastcol].Text, "dd.MM.yyyy", CultureInfo.InvariantCulture, DateTimeStyles.None, out dt))
{
    string dtstr = dt.ToString("dd.MM.yyyy");
    if (dtstr != today)
    {
        e.Row.Cells[lastcol].ForeColor = System.Drawing.Color.Red;
        foreach (GridViewRow row in GridView1.Rows)
        {
            row.Cells[lastcol].ForeColor = System.Drawing.Color.Red;
        }
    }
}