DataGridView行上下移动操作报错，请求技术协助

我在DataGridView中执行行上下移动操作时出现如图错误，求解决。

上移按钮（Btn Up）代码： #

if (dataGridView1.SelectedRows[0].Index != 0)
{
    for (int j = 1; j < this.dataGridView1.Columns.Count; j++)
    {
        object tmp = this.dataGridView1[j, dataGridView1.SelectedRows[0].Index].Value;
        this.dataGridView1[j, dataGridView1.SelectedRows[0].Index].Value = this.dataGridView1[j, dataGridView1.SelectedRows[0].Index - 1].Value;
        this.dataGridView1[j, dataGridView1.SelectedRows[0].Index - 1].Value = tmp;
    }
    int a = dataGridView1.SelectedRows[0].Index;
    dataGridView1.ClearSelection();
    this.dataGridView1.Rows[a - 1].Selected = true;
}

下移按钮（Btn Down）代码： #

if (dataGridView1.SelectedRows[0].Index != dataGridView1.Rows.Count - 2)
{
    for (int j = 1; j < this.dataGridView1.Columns.Count; j++)
    {
        object tmp = this.dataGridView1[j, dataGridView1.SelectedRows[0].Index].Value;
        this.dataGridView1[j, dataGridView1.SelectedRows[0].Index].Value = this.dataGridView1[j, dataGridView1.SelectedRows[0].Index + 1].Value;
        this.dataGridView1[j, dataGridView1.SelectedRows[0].Index + 1].Value = tmp;
    }
    int i = dataGridView1.SelectedRows[0].Index;
    dataGridView1.ClearSelection();
    this.dataGridView1.Rows[i + 1].Selected = true;
}

保存按钮（Btn Save）代码： #

DataTable dt = (DataTable)dataGridView1.DataSource;
try
{
    using (SqlCommandBuilder scb = new SqlCommandBuilder(sda))
    {
        sda.Update(dt);
    }
    MessageBox.Show("Değişiklikler Kaydedildi.");
}
catch (Exception ee)
{
    MessageBox.Show(ee.Message);
}
listele();

问题解决方法 #

1. 修复索引越界问题

• 所有按钮操作前先判断是否有选中行，避免SelectedRows[0]抛出索引越界异常：

  if (dataGridView1.SelectedRows.Count == 0) return;
  

• 下移按钮的判断条件错误，默认DataGridView会包含空的新行，修正判断逻辑：

  int currentIndex = dataGridView1.SelectedRows[0].Index;
  if (currentIndex >= dataGridView1.Rows.Count - 1 || dataGridView1.Rows[currentIndex].IsNewRow) return;
  

2. 改用DataTable操作行（更稳定）

直接操作绑定的数据源而非单元格值，避免事件触发异常和繁琐的单元格遍历：

• 修正后的上移代码：

  private void BtnUp_Click(object sender, EventArgs e)
  {
      if (dataGridView1.SelectedRows.Count == 0) return;
      int currentIndex = dataGridView1.SelectedRows[0].Index;
      if (currentIndex == 0 || dataGridView1.Rows[currentIndex].IsNewRow) return;
  
      DataTable dt = (DataTable)dataGridView1.DataSource;
      DataRow currentRow = dt.Rows[currentIndex];
      
      dt.Rows.Remove(currentRow);
      dt.Rows.InsertAt(currentRow, currentIndex - 1);
  
      dataGridView1.ClearSelection();
      dataGridView1.Rows[currentIndex - 1].Selected = true;
  }
  

• 修正后的下移代码：

  private void BtnDown_Click(object sender, EventArgs e)
  {
      if (dataGridView1.SelectedRows.Count == 0) return;
      int currentIndex = dataGridView1.SelectedRows[0].Index;
      DataTable dt = (DataTable)dataGridView1.DataSource;
      if (currentIndex >= dt.Rows.Count - 1 || dataGridView1.Rows[currentIndex].IsNewRow) return;
  
      DataRow currentRow = dt.Rows[currentIndex];
      
      dt.Rows.Remove(currentRow);
      dt.Rows.InsertAt(currentRow, currentIndex + 1);
  
      dataGridView1.ClearSelection();
      dataGridView1.Rows[currentIndex + 1].Selected = true;
  }
  

3. 保存操作注意点

• 确保SqlDataAdapter（sda）的SelectCommand已正确配置，否则SqlCommandBuilder无法生成有效的更新语句。
• 若保存后listele()方法会重新绑定数据源，可在绑定后恢复之前的选中索引，提升用户体验。

内容的提问来源于stack exchange，提问作者ismail