求大虾解...{"未将对象引用设置到对象的实例。"}C#.NET
protected override void Modify()
  {
   
  DataSet ds = (DataSet)dgv区域.DataSource;  
SqlConnection Sqldb连接 = new SqlConnection("Data Source=(local);Initial Catalog=学生成绩2;Integrated Security=True");
  Sqldb连接.Open();
  SqlCommand sqldb命令 = new SqlCommand("", Sqldb连接);
  if (bAdd)
  {
  sqldb命令.CommandText = "insert into 学生(name,number,scores)values(";
  sqldb命令.CommandText += "'" + txt姓名.Text + "',";
  sqldb命令.CommandText += "'" + txt学号.Text + "',";
  sqldb命令.CommandText += "'" + txt成绩.Text + ",";
  DataRow drRow = ds.Tables[dgv区域.DataMember].NewRow();
  drRow["name"] = txt姓名.Text;
  drRow["number"] = txt学号.Text;
  drRow["scores"] = txt成绩.Text;
  sqldb命令.CommandText = "select number from" + dgv区域.DataMember + "order by number desc";
  drRow["number"] = sqldb命令.ExecuteScalar();
  ds.Tables[dgv区域.DataMember].Rows.InsertAt(drRow, 0);
  }
  else
  {
  sqldb命令.CommandText = "update 学生 set";
  sqldb命令.CommandText += ", name='" + txt姓名.Text + "'";
  sqldb命令.CommandText += ", number='" + txt学号.Text + "'";
  sqldb命令.CommandText += "'scores='" + txt成绩.Text + "'";
  sqldb命令.CommandText += "where number=" + dgv区域.CurrentRow.Cells["number"].Value.ToString();
  ds.Tables[dgv区域.DataMember].Rows[dgv区域.CurrentRow.Index]["number"] = txt学号.Text;
  ds.Tables[dgv区域.DataMember].Rows[dgv区域.CurrentRow.Index]["name"] = txt姓名.Text;
  ds.Tables[dgv区域.DataMember].Rows[dgv区域.CurrentRow.Index]["scores"] = txt成绩.Text;
  }
  sqldb命令.ExecuteNonQuery();
  Sqldb连接.Close();

  }

------解决方案--------------------
看看那个为空了再问.不过话又说回来,我很佩服这种"拼"出来的SQL语句.
------解决方案--------------------

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引用:
protected override void Modify()
{

DataSet ds = (DataSet)dgv区域.DataSource;
SqlConnection Sqldb连接 = new SqlConnection("Data Source=(local);Initial Catal……


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