[英]How to refresh my DataGridView? I am trying to refresh the list in datagridview but i can't
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace PetsHotelSystem.User_Control
{
public partial class UC_UpdateRoom : UserControl
{
function fn = new function();
string query;
public UC_UpdateRoom()
{
InitializeComponent();
}
private void label2_Click(object sender, EventArgs e)
{
}
private void UC_UpdateRoom_Load(object sender, EventArgs e)
{
query = "select * from rooms";
DataSet ds = fn.getData(query);
DataGridView1.DataSource = ds.Tables[0];
}
private void button1_Click(object sender, EventArgs e)
{
if(txtRoomNo.Text != "" && txtType.Text != "" && txtBed.Text != "" && txtPrice.Text !="")
{
string roomno = txtRoomNo.Text;
string type = txtType.Text;
string bed = txtBed.Text;
Int64 price = Int64.Parse(txtPrice.Text);
query = "insert into rooms (roomNO, roomType, bed, price) values ('" + roomno + "','" + type + "','" + bed + "','" + price + "')";
fn.setData(query, "Room Added.");
UC_UpdateRoom_Load(this, null);
}
else
{
MessageBox.Show("Fill all fields.", "Warning !!!", MessageBoxButtons.OK, MessageBoxIcon.Warning);
}
}
private void DataGridView1_CellContentClick(object sender, DataGridViewCellEventArgs e)
{
}
}
}```
運行上面的代碼會返回以下錯誤:
警告:拋出異常:System.Data.dll 中的“System.Data.SqlClient.SqlException”附加信息:無法將值 NULL 插入列“roomID”,表“myHotel.dbo.rooms”; 列不允許空值。 插入失敗。 該語句已終止。
如何解決?
這是因為表中的roomID
列。 如果您希望在手動插入新行時自動遞增,則必須在表定義中將其定義為自動遞增。
您的查詢有異常,因此您必須先解決,但在插入數據后刷新 datagridview,代碼應該是
UC_UpdateRoom_Load(sender, e);
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.