如何從sql數據庫表加載數據到文本框

Question

我有問題我無法將數據加載到文本框中，查詢從窗體中的數據庫中獲取。 while循環無法執行。如何解決這個問題。或沒有任何錯誤或例外。內部命令不能執行調試器移動來捕獲和完成。

private void btnCheck_Click(object sender, EventArgs e) 
    { 
     try 
     { 
      // query = "SELECT Id, Emplname, CNIC, City, MobileNo, Address, Salary, DailyWage, CompanyId, Status FROM Employees where id = '" + labCompyId.Text + "'"; 
     query = "SELECT CNIC, City, MobileNo, Address, Salary, DailyWage, Status FROM Employees WHERE (EmployId = '"+txtEmployId+"') AND (Emplname = '"+txtEmplyName+"')"; 
     SqlCommand command1 = DBConnectivity.getCommandForQuery(query, connection); 
     SqlDataReader reader1 = command1.ExecuteReader(); 


     while(reader1.Read()) 
     { 
     this.txtCNIC.Text = (reader1["CNIC"].ToString()); 
     this.txtEmplyCity.Text = (reader1["City"].ToString()); 
     this.txtEmplyAddress.Text = (reader1["Address"].ToString()); 
     this.txtSalary.Text = (reader1["Salary"].ToString()); 
     this.txtDailyWage.Text = (reader1["DailyWage"].ToString()); 

      reader1.Close(); 
     } 


     } 
     catch (Exception ex) 
     { 

     } 

    } 

Answer 1

哦什麼.Stop !!!使用參數化查詢，以避免SQL注入

提到你在connection

conncection字符串我希望這些問題是你已經missesd txtEmployId.Text價值，並在您選擇查詢txtEmplyName.Text值

SqlConnection connection= new SqlConnection(your Connection string); 
string query = "SELECT CNIC, City, MobileNo, Address, Salary, DailyWage, Status 
     FROM Employees WHERE EmployId =@EmpID AND Emplname = @Emplname "; 
SqlCommand command1 = new SqlCommand(query, connection); 
connection.Open(); 
command1.Parameters.AddWithValue("@EmpID",txtEmployId.Text); 
command1.Parameters.AddWithValue("@Emplname",txtEmplyName.Text); 
SqlDataReader reader1 = command1.ExecuteReader(); 


    while(reader1.Read()) 
    { 
    this.txtCNIC.Text = (reader1["CNIC"].ToString()); 
    this.txtEmplyCity.Text = (reader1["City"].ToString()); 
    this.txtEmplyAddress.Text = (reader1["Address"].ToString()); 
    this.txtSalary.Text = (reader1["Salary"].ToString()); 
    this.txtDailyWage.Text = (reader1["DailyWage"].ToString()); 

     reader1.Close(); 
    } 

Answer 2

1. 哪裏是你的ConnectionString的？如果它不在頁面中，請包含一個。
2. 打開連接像Con.open（）
3. 使用參數化查詢來避免sql注入，但這只是一個建議。

代碼的問題是我認爲的連接字符串。打開try塊內的連接。