在c中複製記錄＃

Question

我正在考勤系統，現在這是我的問題，我搜索了一個人的名字，並嘗試登錄他的出席，它首先是好的，登錄後第二命名它仍然很好。但是一旦我嘗試編輯第一個或第二個用戶的登錄出席時，我的datagridview（連接到我的數據庫）中的所有值都重複了。如果我在week1中輸入name1參加考試，那很好。第1周的參加者名字2仍然沒問題。 但如果我編輯相同的名稱。甚至去下一週的數字，所有保存的值都根據我最近輸入的名稱重複。對於 插入新記錄

SqlConnection cnn200 = new SqlConnection(connectionstring); 
      string sql200 = "SELECT * FROM attendance WHERE csign=@csign "; 
      cnn200.Open(); 
      SqlCommand cmd200 = new SqlCommand(sql200, cnn200); 
      SqlDataReader rdr200; 
      cmd200.Parameters.AddWithValue("@csign", callsign); 

      rdr200 = cmd200.ExecuteReader(); 

       if (rdr200.Read() == true) 

       { 
      SqlConnection cnn201 = new SqlConnection(connectionstring); 
        if (textBox89.Text == "1") 
        { 
         string sql201 = "insert INTO attendance 
      (csign,name,week1)" + "VALUES" + "(@csign,@name,@week1)"; 
         cnn201.Open(); 
         SqlCommand cmd201 = new SqlCommand(sql201, cnn201); 
         cmd201.Parameters.AddWithValue("@csign", callsign); 
     cmd201.Parameters.AddWithValue("@name", namee); 
         cmd201.Parameters.AddWithValue("@week1", 
      comboBox1.Text); 

         cmd201.ExecuteNonQuery(); 
        } 
       if (textBox89.Text == "2") 
       { 
        string sql201 = "insert INTO attendance 
       (csign,name,week2)" + "VALUES" + "(@csign,@name,@week2)"; 
        cnn201.Open(); 
        SqlCommand cmd201 = new SqlCommand(sql201, cnn201); 
        cmd201.Parameters.AddWithValue("@csign", callsign); 
      cmd201.Parameters.AddWithValue("@name", namee); 
        cmd201.Parameters.AddWithValue("@week2", 
       comboBox1.Text); 

        cmd201.ExecuteNonQuery(); 
       } 

和更新

   else{ 
      SqlConnection cnn201 = new SqlConnection(connectionstring); 
        if (textBox89.Text == "1") 
        { 
         string sql201 = "UPDATE attendance SET 
      name=@name,csign=@csign,week1=@week1"; 
         cnn201.Open(); 
         SqlCommand cmd201 = new SqlCommand(sql201, cnn201); 

         cmd201.Parameters.AddWithValue("@name", namee); 
        cmd201.Parameters.AddWithValue("@csign", callsign); 
         cmd201.Parameters.AddWithValue("@week1", 
        comboBox1.Text); 

         cmd201.ExecuteNonQuery(); 
        } 
       if (textBox89.Text == "2") 
       { 
        string sql201 = "UPDATE attendance SET 
        name=@name,csign=@csign,week2=@week2"; 
        cnn201.Open(); 
        SqlCommand cmd201 = new SqlCommand(sql201, cnn201); 

        cmd201.Parameters.AddWithValue("@name", namee); 
        cmd201.Parameters.AddWithValue("@csign", callsign); 
        cmd201.Parameters.AddWithValue("@week2", 
        comboBox1.Text); 

        cmd201.ExecuteNonQuery(); 
       }`} 

Answer 1

尼加，我想我可以提供幫助。使用較少的編碼線就可以輕鬆完成您想要做的事情。一個完整的DataGridView可以顯示，編輯，刪除，必須使用幾個對象

using System; 
using System.Collections.Generic; 
using System.ComponentModel; 
using System.Data; 
using System.Drawing; 
using System.Windows.Forms; 
using System.Globalization; 
using System.Data.SqlClient; 
using System.IO; 
using System.Configuration; 


namespace ADO_NET_Testbed 
{ 
    public partial class MainForm : Form 
    { 
     private SqlDataAdapter adapter; 
     private string connectionString = @"Data Source=Server;Persist Security Info=True;Password=password!;User ID=sooperuser;Initial Catalog=Database"; 
     private string sqlcommand = @"SELECT OPID, LastName, FirstName, Title, PhoneOffice, PhoneCell, Email, Active, Admin, Tester, Educator, Developer FROM AuditUser"; 
     private SqlCommandBuilder cmdBuilder = new SqlCommandBuilder(); 
     private DataTable datatable = new DataTable(); 
     private DataSet dataset = new DataSet(); 

     public MainForm() 
     { 
      InitializeComponent(); 
     } 

     private void MainForm_Load(object sender, EventArgs e) 
     { 
      adapter = new SqlDataAdapter(sqlcommand, connectionString); 
      adapter.Fill(dataset, "AuditUser"); 
      dgvUsers.DataSource = dataset.Tables[0]; 
      dgvUsers.Enabled = true; 
      this.Show(); 
     } 

     private void btnCancel_Click(object sender, EventArgs e) 
     { 
      dataset.Clear(); 
      dataset.Reset(); 
      this.Close(); 
     } 

     private void btnSave_Click(object sender, EventArgs e) 
     { 
      cmdBuilder.DataAdapter = adapter; 
      adapter.Update(dataset.Tables[0]); 
      this.Close(); 
     } 
    } 
} 

至於到底是怎麼回事的快速綱要中，SqlDataAdapter的持有四個查詢沒有重複，但自動創建三個來自SELECT命令。使用SqlCommandBuilder可以添加其他三個，儘管調試器不會將它們顯示爲NULL而不顯示它們。 adapter.Fill（）和adapter.Update（）根據datagridview中每行的RowState處理所有不同的命令。無論如何，這個表單無論如何都是關閉的，「取消」看起來太過分了。