C#中DBNull问题

<summary> /// 插入数据 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void button2_Click(object sender, RoutedEventArgs e) { string name = txtName.Text; string age = txtAge.Text; string height = txtHeight.Text; object objName; if (name.Length <= 0) { objName = DBNull.Value; } else { objName = name; } object objAge; if (age.Length <= 0) { objAge = DBNull.Value; } else { objAge = age; } object objHeight; if (height.Length <= 0) { objHeight = DBNull.Value; } else { objHeight = height; } SqlHelper.ExecuteNonQuery(@"insert into T_Person(Name,Age,Height) values (@Name,@Age,@Height)", new SqlParameter("@Name", objName), new SqlParameter("@Age", objAge), new SqlParameter("@Height", objHeight)); } /// <summary> /// 读出数据 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void button3_Click(object sender, RoutedEventArgs e) { DataSet ds = SqlHelper.ExecuteDataSet("select * from T_Person where id=2"); string name; if (ds.Tables[0].Rows[0]["Name"] == DBNull.Value) { name = null; } else { name = ds.Tables[0].Rows[0]["Name"].ToString(); } int? age; if (ds.Tables[0].Rows[0]["Age"] == DBNull.Value) { age = null; } else { age = int.Parse(ds.Tables[0].Rows[0]["Age"].ToString()); } txtName.Text = name; txtAge.Text = age.ToString(); txtHeight.Text=ds.Tables[0].Rows[0]["Height"].ToString(); }

C#中DBNull问题

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