Question

我正在开发一个具有登录页面的Windows应用程序，用户在其中输入sql连接凭据用户名和密码。然后他们可以将数据从excel表上传到db。当用户按下运行按钮时，我遇到的问题是启动打开文件和读取数据的过程，而不是最终将值传递给DB，当它尝试连接到数据库时失败，因为他为用户名返回null密码。如何在将程序传递给数据库连接部分时让程序记住这些值？

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.IO;
using System.Threading;
using System.Globalization;
using System.Data.SqlClient;

namespace NewTestDataReader
{
   public partial class DataUploader : Form
{
    public DataUploader()
    {
        InitializeComponent();
    }

    internal string m_susername;
    public string username { get { return this.m_susername; } set { this.m_susername = value; } }
    internal string m_spassword;
    public string password { get { return this.m_spassword; } set { this.m_spassword = value; } }

   private void RunButton_Click(object sender, EventArgs e)
    {
        Thread oThread = new Thread(new ThreadStart(scan));
        oThread.Start();   
        password = userPasswordInputTextBox.Text;
        username = userNameInputTextBox.Text;
    }
    private void scan()
    {
        ///scans the file and goes to FileReader function in separate   TestDataReader.cs file
     }
  }
}

 using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Text;
 using System.Data.SqlClient;
 using System.Data;
 using System.IO;
 using System.Text.RegularExpressions;
 using Excel = Microsoft.Office.Interop.Excel;

 namespace TestDataReader 
{
public class SheetOneDataReader : DataUploader
{
  //parameters it reads from the excel sheet
    internal string m_sName;
    public string Name { get { return m_sName; } set { m_sName = value; } }

    internal string m_sAddress;
    public string Address{ get { return m_sAddress; } set { m_sAddress = value; } }

public void SaveSheetOneDataToDB()
    {
       SqlCommand cmd = new SqlCommand("UL_ExcelFirstSheetData");
        cmd.CommandType = CommandType.StoredProcedure;
        cmd.Parameters.Add("@Name", SqlDbType.NVarChar, 50).Value = this.Name;
        cmd.Parameters.Add("@Address", SqlDbType.NVarChar, 50).Value = this.Address;

      String connectionString;  
       SqlConnection cnn;        
        connectionString = "data source = 10.5.200.300";
        connectionString += ";initial catalog = Excel_data" + ";Persist Security Info=True";
        **connectionString += ";user id=" +  username;  //returns null 
        connectionString += ";password=" + password;   //returns null**
         cnn = new SqlConnection(connectionString);
        try
        {
            cnn.Open();
        }
        catch
        {}         
    }
}

 public class FileReader
  {
      public static bool ReadFile(FileInfo oInfo)
    {
        try
        {
          //goes to SheetOneDataReader on top
           SheetOneDataReader oDataSheetOne = new SheetOneDataReader();
           oDataSheetOne.Name =  //values from excel sheet
           oDataSheetOne.Address = //values from the excel sheet
           oDataSheetOne.SaveSheetOneDataToDB();

        }
    }
 }
}

Answer 1

username和password属性属于您在DataUploader中继承的班级SheetOneDataReader。您可以在RunButton_Click下的DataUploader中设置这些属性的值。当你继承那个类时，它将使用null重新初始化这两个属性，而不是保留你在其他类中指定的值。

而是为SheetOneDataReader类中的以下属性设置值，这是您需要它们连接到数据库的位置。

password = userPasswordInputTextBox.Text;
username = userNameInputTextBox.Text;

或者您可能不得不采用其他一些州管理方式，例如Session或ViewState

Textbox.text参数未传递给db connection C＃application

1 个答案: