SQL

我已經寫好SQL的資料庫了
只是我要利用物件去查詢資料庫內的人員資料

所以您不會使用自己寫的Class嗎?那麻煩您貼一下程式碼方便大家參詳參詳

namespace 資料庫_client資料 { public partial class 服務器 : Form { public class SocketT2h { public Socket Socket { get; set; } //建立socket物件 public string Name { get; set; } //儲存用戶端姓名 public SocketT2h(Socket socket) //儲存客戶連入 { this.Socket = socket; //為socket物件 } } private byte[] buffer = new byte[1024]; //建立接收buffer public List<SocketT2h> ClientSocket { get; set; } //建立客戶串列 List<string> names = new List<string>(); //建立名字串列 private Socket serverSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);//建立socket物件文IPv4位置、類別為支援雙向資料、通訊協定為tcp public 服務器() { InitializeComponent(); CheckForIllegalCrossThreadCalls = false; ClientSocket = new List<SocketT2h>(); } private void Start() { serverSocket.Bind(new IPEndPoint(IPAddress.Any, 1980)); //建立服務器IP與Port(端口:1980) serverSocket.Listen(1); //接聽 serverSocket.BeginAccept(new AsyncCallback(AppceptCallback), null); //開始非同步作業，接收連入 richText.AppendText("---開啟服務---" + "\r\n"); richText.AppendText("---等待連入---" + "\r\n"); } private void AppceptCallback(IAsyncResult ar) { Socket socket = serverSocket.EndAccept(ar); //已非同步方式接受連入，並建立新的Socket來處理遠端 ClientSocket.Add(new SocketT2h(socket)); //串列加入client連入資訊 listIp.Items.Add(socket.RemoteEndPoint.ToString());//listbox顯示客戶的IP與端口 socket.BeginReceive(buffer, 0, buffer.Length, SocketFlags.None, new AsyncCallback(ReceiveCallback), socket);//接收客戶傳入的資料 serverSocket.BeginAccept(new AsyncCallback(AppceptCallback), null);//開始非同步作業，接收連入(需再列入等待，否則無法接受更多連入) } private void ReceiveCallback(IAsyncResult ar) { Socket socket = (Socket)ar.AsyncState; if (socket.Connected) //如果有人連入 { int received; received = socket.EndReceive(ar); byte[] dataBuf = new byte[received]; Array.Copy(buffer, dataBuf, received); string text = Encoding.ASCII.GetString(dataBuf); richText.AppendText("客戶: " + text + "\r\n"); //加入文字 } socket.BeginReceive(buffer, 0, buffer.Length, SocketFlags.None, new AsyncCallback(ReceiveCallback), socket); } void Sendata(Socket socket, string noidung) { byte[] data = Encoding.ASCII.GetBytes(noidung); socket.BeginSend(data, 0, data.Length, SocketFlags.None, new AsyncCallback(SendCallback), socket); serverSocket.BeginAccept(new AsyncCallback(AppceptCallback), null); } private void SendCallback(IAsyncResult AR) { Socket socket = (Socket)AR.AsyncState; socket.EndSend(AR); } private void 服務器_Load_1(object sender, EventArgs e) { Start(); //使用執行續 } private void btnSend_Click_1(object sender, EventArgs e) { for (int j = 0; j < ClientSocket.Count; j++) { { Sendata(ClientSocket[j].Socket, txtSend.Text); } } richText.AppendText("服務端: " + txtSend.Text + "\r\n"); //加入文字 txtSend.Text = ""; //清空 } private void 服務器_FormClosed(object sender, FormClosedEventArgs e) { Application.Exit(); } private void txtSend_KeyDown_1(object sender, KeyEventArgs e) { if (e.KeyCode == Keys.Enter) //當按下Enter時 { btnSend_Click_1(sender, e); //執行送出紐 } }

上面貼錯程式



namespace 資料庫_client資料 { public partial class Form1 : Form { public Form1() { InitializeComponent(); } String cnStr = @"Data Source=(LocalDB)\v11.0;AttachDbFilename=|DataDirectory|\MyDB.mdf;Integrated Security=True"; //string[] singer = new string[] {"+866","02","03","04" }; private void Form1_Load(object sender, EventArgs e) { // TODO: 這行程式碼會將資料載入 'myDBDataSet6.client' 資料表。您可以視需要進行移動或移除。 this.clientTableAdapter.Fill(this.myDBDataSet6.client); SqlConnection cn = new SqlConnection(cnStr); SqlDataAdapter da = new SqlDataAdapter("SELECT *From client", cn); DataSet ds = new DataSet(); da.Fill(ds); dataGridView1.DataSource = ds.Tables[0]; } private void btnAdd_Click(object sender, EventArgs e) { try { SqlConnection cn = new SqlConnection(cnStr); cn.Open(); SqlCommand cmd = new SqlCommand(); cmd.CommandText = "INSERT INTO client(編號,姓名,性別,電話區碼,電話,信箱,地址,車牌)VALUES(N'" + txtId.Text.Replace("'", "''") + "',N'" + txtName.Text.Replace("'", "''") + "',N'" + txtSex.Text.Replace("'", "''") + "',N'" + txtN.Text+ "',N'" + txtNumber.Text.Replace("'", "''") + "',N'" + txtMail.Text.Replace("'", "''") + "',N'" + txtAddress.Text + "',N'" + txtCar.Text.Replace("'", "'") +"')"; cmd.Connection = cn; cmd.ExecuteNonQuery(); Form1_Load(sender, e); } catch (Exception ex) { MessageBox.Show(ex.Message); } } private void btnclear_Click(object sender, EventArgs e) { txtAddress.Text = ""; txtId.Text = ""; txtN.Text = ""; txtMail.Text = ""; txtName.Text = ""; txtNumber.Text = ""; txtSex.Text = ""; txtCar.Text = ""; } private void btnModify_Click(object sender, EventArgs e) { try { SqlConnection cn = new SqlConnection(cnStr); cn.Open(); SqlCommand cmd = new SqlCommand(); cmd.CommandText = "UPDATE client SET 姓名=N'" + txtName.Text.Replace("'", "''") + "', 性別=N'" + txtSex.Text.Replace("'", "''") + "', 信箱=N'" + txtMail.Text.Replace("'", "''") + "', 地址=N'" + txtAddress.Text.Replace("'", "''") + "',車牌=N'" + txtCar.Text.Replace("'", "''") + "', 電話區碼=N'" + txtN.Text.Replace("'", "''") + "', 電話=" + txtNumber.Text.Replace("'", "''") + "WHERE 編號=N'" + txtId.Text.Replace("'", "''") + "'"; cmd.Connection = cn; cmd.ExecuteNonQuery(); Form1_Load(sender, e); } catch (Exception ex) { MessageBox.Show(ex.Message); } } private void btnDelete_Click(object sender, EventArgs e) { try { SqlConnection cn = new SqlConnection(cnStr); cn.Open(); SqlCommand cmd = new SqlCommand(); cmd.CommandText = "DELETE FROM client WHERE 編號=N'" + txtId.Text.Replace("'", "''") + "'"; cmd.Connection = cn; cmd.ExecuteNonQuery(); Form1_Load(sender, e); } catch (Exception ex) { MessageBox.Show(ex.Message); }

這是同個老師的作業嗎？

資料庫的程式碼和這棟樓的
語法資料庫問題
一般無二阿

你不是都寫好了嗎?
//讀取資料庫資料 SqlConnection cn = new SqlConnection(cnStr); SqlDataAdapter da = new SqlDataAdapter("SELECT *From client", cn); DataSet ds = new DataSet(); da.Fill(ds); //綁定資料來源 dataGridView1.DataSource = ds.Tables[0];
還是你要的是更新資料?
//清除 dataGridView1.DataSource = null; dataGridView1.Rows.Clear(); //讀取資料庫資料 SqlConnection cn = new SqlConnection(cnStr); SqlDataAdapter da = new SqlDataAdapter("SELECT *From client", cn); DataSet ds = new DataSet(); da.Fill(ds); //綁定資料來源 dataGridView1.DataSource = ds.Tables[0];
請再把問題明確一點

謝謝各位大大

突然有閣問題可以請大大在幫幫忙嗎
private void button1_Click(object sender, EventArgs e) { using (SqlConnection cn = new SqlConnection()) { cn.ConnectionString = @"Data Source=(LocalDB)\v11.0;AttachDbFilename=|DataDirectory|\MyDB.mdf;Integrated Security=True"; cn.Open(); string searchName = txtBox1.Text; string selectCmd = "SELECT * FROM client WHERE 姓名 = '" + searchName + "'"; SqlDataAdapter da = new SqlDataAdapter(selectCmd, cn); SqlCommand cmd = new SqlCommand(); SqlDataReader dr = cmd.ExecuteReader(); if (dr.Read()) { txtS.Text = "編號:" + dr["編號"].ToString() + Environment.NewLine; } else { txtS.Text = "找不到" + txtBox1.Text + "這個人"; }


執行後顯示的視窗上寫{類型 'System.InvalidOperationException' 的未處理例外狀況發生於 System.Data.dll

其他資訊: ExecuteReader: Connection 屬性尚未初始化。}

改這樣
private void button1_Click(object sender, EventArgs e) { using (SqlConnection cn = new SqlConnection()) { SqlCommand cmd = new SqlCommand(); cmd.SqlConnection = cn; cn.ConnectionString = @"Data Source=(LocalDB)\v11.0;AttachDbFilename=|DataDirectory|\MyDB.mdf;Integrated Security=True"; cn.Open(); string searchName = txtBox1.Text; string selectCmd = "SELECT * FROM client WHERE 姓名 = '" + searchName + "'"; SqlDataAdapter da = new SqlDataAdapter(selectCmd, cn); SqlDataReader dr = cmd.ExecuteReader(); if (dr.Read()) { txtS.Text = "編號:" + dr["編號"].ToString() + Environment.NewLine; } else { txtS.Text = "找不到" + txtBox1.Text + "這個人"; }

第 7 行的程式中的 SqlConnection 顯示出未定義是哪裡的問題

請問各位大大
我自己從課本找到的
可是程式完成後我的查詢只會顯示一個人的資料是出哪裡有問題
private void button1_Click(object sender, EventArgs e) { if (txtXXX.Text == "") { txtS.Text = "請輸入姓名"; return; } using (SqlConnection cn = new SqlConnection()) { cn.ConnectionString = @"Data Source=(LocalDB)\v11.0;" + "AttachDbFilename=|DataDirectory|MyDB.mdf;" + "Integrated Security=True"; cn.Open(); SqlCommand cmd = new SqlCommand(); cmd.Connection = cn; cmd.CommandText = "GetEmployeeByName"; cmd.CommandType = CommandType.StoredProcedure; cmd.Parameters.Add(new SqlParameter("@EmpName", SqlDbType.NVarChar)); cmd.Parameters["@EmpName"].Value = txtXXX.Text; txtS.Text = ""; SqlDataReader dr = cmd.ExecuteReader(); if (dr.Read()) { for (int i = 0; i < dr.FieldCount; i++) { txtS.Text += dr.GetName(i) + ":" + dr[i].ToString() + Environment.NewLine; } } else { txtS.Text = "找不到" + txtXXX.Text + "這個人"; }

去看你的StoredProcedure裡寫什麼

改成這樣試看看
[code]
while (dr.Read())
{
txtS.Text += dr.GetName(i) + ":" + dr[i].ToString() + Environment.NewLine;
}
[/code]