请教个datagirdiview控件的问题！

Question

foreach (DataGridViewRow dgr in dgvBuySell.Rows)
                {
                    if (dgr.Cells["BuySellStates"].Value.ToString() == "Buy") //买
                    {
                        dgr.Cells["BuySellBtnBuySell"].Value = "买入";
                        dgr.Cells["BuySellBtnBuySell"].Style.BackColor = System.Drawing.Color.Red; //行变红色
                    }
                    if (dgr.Cells["BuySellStates"].Value.ToString() == "Sell") //卖
                    {
                        dgr.Cells["BuySellBtnBuySell"].Value = "卖出";
                        dgr.Cells["BuySellBtnBuySell"].Style.BackColor = System.Drawing.Color.Blue; //行变蓝色
                    }
                }
我这样循环datagridview  然后判断现在有个这样的问题，如果我在datagridview的属性里设置AllowUserToAddRows = False 上面的代码就失效了，如果为True才有用，请问为什么会这样？如果要设置False如何才能让上面的代码判断有效？

Answer 1

DataGridView.AllowUserToAddRows 属性 
获取或设置一个值，该值指示是否向用户显示添加行的选项。 

Answer 2

关注
不过，添加行 一般不用DataGridView.AllowUserToAddRows 属性 而是通过代码来实现

Answer 3

因为你设置用户不允许修改添加行 猜想就重新绘制datagridview 所以设置颜色没有起效果

Answer 4

你得加一个if判断单元格是否为空,AllowUserToAddRows=true后产生的那一行的值为null:foreach (DataGridViewRow dgr in dgvBuySell.Rows)
                {
if(dgr.Cells["BuySellStates"].Value!=null){
                    if (dgr.Cells["BuySellStates"].Value.ToString() == "Buy") //买
                    {
                        dgr.Cells["BuySellBtnBuySell"].Value = "买入";
                        dgr.Cells["BuySellBtnBuySell"].Style.BackColor = System.Drawing.Color.Red; //行变红色
                    }
                    if (dgr.Cells["BuySellStates"].Value.ToString() == "Sell") //卖
                    {
                        dgr.Cells["BuySellBtnBuySell"].Value = "卖出";
                        dgr.Cells["BuySellBtnBuySell"].Style.BackColor = System.Drawing.Color.Blue; //行变蓝色
                    }
}
                }

Answer 5

你是在那个事件里面写的代码？dataGridView_CellPainting？

Answer 6

加了 if(dgr.Cells["BuySellStates"].Value!=null){ } 也不行啊，还是无效

Answer 7

你这个是写在什么事件里了啊？像这种需求一般写在CellFormating里比较合适

Answer 8

我没有放在CellFormating事件里，那样控件会狂闪，好奇怪！

Answer 9

你上面列出的代码,是放在什么事件里呢?若放在CellFormating事件里,可这样写,不需循环: private void dataGridView1_CellFormatting(object sender, DataGridViewCellFormattingEventArgs e)
        {
            if (e.ColumnIndex == 0)
            {
                if (e.Value != null)
                {
                    if (e.Value.ToString() == "XB")
                    {
                        e.CellStyle.BackColor = Color.Red;
                    }
                    else
                    {
                        e.CellStyle.BackColor = Color.Blue;
                    }
                }
            }            
        }

Answer 10

理想的是放在CellFormatting事件里,但代码要改,不能采用循环全部,因为CellFormatting事件是每一行触发.
想一下每CellFormatting事件就要去遍列所有行,整个显示下来就要重复N多次,当然会狂闪了!按下面代码的思路去调试一下吧,祝你成功!private void dgvBuySell_CellFormatting(object sender, DataGridViewCellFormattingEventArgs e)
        {
            if (dgvBuySell[e.RowIndex]["BuySellStates"].ToString()== "Buy")
            {
                 dgvBuySell[e.RowIndex]["BuySellBtnBuySell"].Value = "买入";
                e.CellStyle.BackColor = System.Drawing.Color.Red; //当前行变红色       
            }
          if (dgvBuySell[e.RowIndex]["BuySellStates"].ToString()=="Sell")
            {
                  dgvBuySell[e.RowIndex]["BuySellBtnBuySell"].Value = "卖出";
                e.CellStyle.BackColor = System.Drawing.Color.Blue; //当前行行变蓝色
              }      
 }

Answer 11

dgvBuySell[e.RowIndex]["BuySellStates"]这样写不对哦

Answer 12

以上更正为:
dgvBuySell["BuySellStates",e.RowIndex].Value

Answer 13

 DataView 取值　dv_tmp[RecordIndex]["BuySellStates"].ToString()
 DataGridView 取值　dgvBuySell["BuySellStates",RowIndex].Value