如何根据两个单元格中的值绘制 DataGridView 中的选定行？

Question

我正在使用 semicolon-delimited 文本文件填充 DataGridView，如下所示：

private void ExistingAppntmntRecs_Load(object sender, EventArgs e)
{
    DataTable dt = SeparatedValsFileToDataTable(APPOINTMENTS_FILE_NAME, ";");
    dataGridViewExistingAppntmntRecs.DataSource = dt;
}

// from  (Frank)
public static DataTable SeparatedValsFileToDataTable(string filename, string separatorChar)
{
    var table = new DataTable("Filecsv");
    using (var sr = new StreamReader(filename, Encoding.Default))
    {
        string line;
        var i = 0;
        while (sr.Peek() >= 0)
        {
            try
            {
                line = sr.ReadLine();
                if (string.IsNullOrEmpty(line)) continue;
                var values = line.Split(new[] { separatorChar }, StringSplitOptions.None);
                var row = table.NewRow();
                for (var colNum = 0; colNum < values.Length; colNum++)
                {
                    var value = values[colNum];
                    if (i == 0)
                    {
                        table.Columns.Add(value, typeof(String));
                    }
                    else
                    { row[table.Columns[colNum]] = value; }
                }
                if (i != 0) table.Rows.Add(row);
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
            i++;
        }
    }
    return table;
}

我现在要做的是将 EndDate 值在当前日期的两个月内的行着色为黄色，在一个月内为橙色，将日期在过去（意味着它们已经失效）的行着色为红色.

有一个可能有效的 PostPaint 事件，但我不知道如何在该事件处理程序中检查行内的单元格内容：

private void dataGridViewExistingAppntmntRecs_RowPostPaint(object sender, DataGridViewRowPostPaintEventArgs e)
{
    // What now?
}

这是读取的文件的内容（bogus/test 数据，前面有 header 行）：

person;phone;email;org;addr1;addr2;city;st8;zip;visitNum;success;adSizeLoc;meetingLoc;meetingDate;meetingTime;adBeginMonth;adBeginYear;adEndMonth;adEndYear;Notes
B.B. King;2221113333;bbking@blues.com;Virtuosos;1234 Wayback Lane;;Chicago;IL;98765;1;false;Full Page Inside Front Cover;Same as Org Address;4/5/2017 2:03:12 PM;9:00 am;May;2017;May;2018;Lucille was her name
Linda Ronstadt;55577889999;rhondalinstadt@eaglet.com;Eagles Singer;La Canada;;Los Angeles;CA;99988;1;false;Full page Inside Back Cover;Same as Org Address;4/5/2017 2:05:23 PM;9:00 am;May;2017;May;2018;She had some good stuff

如果 adEndMonth + adEndYear 日期等于或少于 2 个月，则整行应为黄色；如果离开 1 个月或更短时间，则为橙色；如果是今天或过去，就把它涂成红色。最后，如果滚石乐队之一是运行应用程序，请将其涂成黑色。

这是 PostPaint 事件的一些伪代码，"TODO:" 我不知道该怎么做：

private void dataGridViewExistingAppntmntRecs_RowPostPaint(object sender, DataGridViewRowPostPaintEventArgs e)
{
    DateTime twoMonthsLimit = DateTime.Now.AddMonths(2);
    DateTime oneMonthLimit = DateTime.Now.AddMonths(1);
    int endYear = // TODO: assign adEndYear value
    int endMonth = // TODO: assign adEndMonth value
    DateTime endDate = new DateTime(endYear, endMonth, 1);
    if (twoMonthsLimit > endDate) // TODO: paint row yellow
    if (oneMonthLimit > endDate) // TODO: paint row orange
    if (endDate < DateTime.Now) // TODO: paint row red
}

Answer 1

如果目标过于简单，突出显示特定日期内的行，然后更改行背景颜色可能是一个更简单的选择。重新绘制行可能是不必要的。我的解决方案只是根据“endMonth”和“endYear”列中的日期更改行背景颜色。

单元格格式设置是一个选项，但它会经常触发，因此无需在每次更改或显示单元格时都进行“着色”检查。如果行已经“着色”，那么唯一要查找的是何时添加新行或更改“endMonth”或“endYear”列中的值。

下面的代码简单地遍历 DataGridView 并根据您描述的条件设置每一行的颜色。获取行颜色的逻辑相当简单（减去将其涂成黑色）。如果日期比今天日期早两个月以上，则将背景色保留为白色。如果日期大于 1 个月但小于 2 个月，则将该行涂成黄色……等

我使用了类似的方法来读取文本文件并创建数据表。希望这有帮助。

DataTable dt;
string filePath = @"D:\Test\Artist.txt";
char delimiter = ';';

public Form1() {
  InitializeComponent();
}

private void Form1_Load(object sender, EventArgs e) {
  dt = GetTableFromFile(filePath, delimiter);
  dataGridViewExistingAppntmntRecs.DataSource = dt;
  UpdateDataGridColors();
}

private DataTable GetTableFromFile(string filePath, char delimiter) {
  List<string[]> allArtists = GetArtistList(filePath, delimiter);
  DataTable dt = GetTableColumns(allArtists[0]);
  int totalCols = dt.Columns.Count;
  DataRow dr;
  for (int i = 1; i < allArtists.Count; i++) {
    string[] curArtist = allArtists[i];
    dr = dt.NewRow();
    for (int j = 0; j < totalCols; j++) {
      dr[j] = curArtist[j].ToString();
    }
    dt.Rows.Add(dr);
  }
  return dt;
}

private List<string[]> GetArtistList(string inFilePath, char inDelimiter) {
  string pathToFile = inFilePath;
  char delimiter = inDelimiter;
  List<string[]> listStringArrays = File.ReadAllLines(pathToFile).Select(x => x.Split(delimiter)).ToList();
  return listStringArrays;
}

private DataTable GetTableColumns(string[] allHeaders) {
  DataTable dt = new DataTable();
  foreach (string curHeader in allHeaders) {
    dt.Columns.Add(curHeader, typeof(string));
  }
  return dt;
}

private Color GetColorForRow(DataRowView dr) {
  // paint it black ;-)
  if (dr[0].ToString().Equals("Rolling Stones")) {
    return Color.Black;
  }
  DateTime rowDate;
  DateTime dateNow = DateTime.Now;
  DateTime twoMonthsLimit = dateNow.AddMonths(2);
  DateTime oneMonthLimit = dateNow.AddMonths(1);
  if (dr != null) {
    string rowStringMonth = dr[17].ToString();
    string rowStringYear = dr[18].ToString();
    string rowStringDate = "1/" + rowStringMonth + "/" + rowStringYear;
    if (DateTime.TryParse(rowStringDate, out rowDate)) {
      if (rowDate > twoMonthsLimit)
        return Color.White;
      if (rowDate > oneMonthLimit)
        return Color.Yellow;
      if (rowDate > dateNow)
        return Color.Orange;
      if (rowDate.Month == dateNow.Month && rowDate.Year == dateNow.Year)
        return Color.Orange;
      // this row date is less than todays month date
      return Color.Red;
    } // else date time parse unsuccessful - ignoring
  }
  // date is null
  return Color.White;
}

private void UpdateDataGridColors() {
  Color rowColor;
  DataRowView dr;
  foreach (DataGridViewRow dgvr in dataGridViewExistingAppntmntRecs.Rows) {
    dr = dgvr.DataBoundItem as DataRowView;
    if (dr != null) {
      rowColor = GetColorForRow(dr);
      dgvr.DefaultCellStyle.BackColor = rowColor;
      if (rowColor == Color.Black)
        dgvr.DefaultCellStyle.ForeColor = Color.White;
    }
  }
}

private void dataGridViewExistingAppntmntRecs_CellValueChanged(object sender, DataGridViewCellEventArgs e) {
  if (e.ColumnIndex == 17 || e.ColumnIndex == 18) {
    //MessageBox.Show("End Date Changed");
    UpdateDataGridColors();
  }
}

private void dataGridViewExistingAppntmntRecs_RowsAdded(object sender, DataGridViewRowsAddedEventArgs e) {
  UpdateDataGridColors();
}

如何根据两个单元格中的值绘制 DataGridView 中的选定行？

How can I paint selected rows in a DataGridView based on the values in two of the cells?

c#

datagridview

datagridviewcolumn

paintevent

winforms