在DataGridView单元格中显示占位符文本

Question

我需要显示一个占位符，该占位符在Winforms中的第一行数据网格视图的前两列中包含一个字符串。当数据网格为空时，将显示占位符。

Answer 1

您需要处理CellPainting事件和借鉴的地方持有者自己：

void dataGridView1_CellPainting(object sender, DataGridViewCellPaintingEventArgs e) 
{ 
    if (e.RowIndex < 0 || e.ColumnIndex < 0)  /*If a header cell*/ 
     return; 
    if (!(e.ColumnIndex == 0 || e.ColumnIndex == 1) /*If not our desired columns*/ 
     return; 

    if(e.Value == null || e.Value == DBNull.Value) /*If value is null*/ 
    { 
     e.Paint(e.CellBounds, DataGridViewPaintParts.All 
      & ~(DataGridViewPaintParts.ContentForeground)); 

     TextRenderer.DrawText(e.Graphics, "Enter a value", e.CellStyle.Font, 
      e.CellBounds, SystemColors.GrayText, TextFormatFlags.Left); 

     e.Handled = true; 
    } 
} 

Answer 2

所以，你可以提高这个（为Textbox工作），并更改dataGrid.Text：

Textbox myTxtbx = new Textbox(); 
myTxtbx.Text = "Enter text here..."; 

myTxtbx.GotFocus += GotFocus.EventHandle(RemoveText); 
myTxtbx.LostFocus += LostFocus.EventHandle(AddText); 

public void RemoveText(object sender, EventArgs e) 
{ 
    if (myTxtbx.Text == "Enter text here...") { 
     myTxtbx.Text = ""; 
    } 
} 

public void AddText(object sender, EventArgs e) 
{ 
    if(String.IsNullOrWhiteSpace(myTxtbx.Text)) 
     myTxtbx.Text = "Enter text here..."; 
} 

注：在myTxtbx.Text = "Enter text here...";和if (myTxtbx.Text == "Enter text here...")字符串“在这里输入文字... “必须相等。