Question

在我的Windows窗体应用程序中，我有一个用户输入的表单，例如名称地址......等等。

当用户按下添加条目时，所有输入条目将被添加到数据库中，同时，订单号将被传递到另一个表单，在那里我有一个SQL查询来获取该特定订单的数据并填充他们在各自的文本框中。

但是当我将订单号从form1传递给form2，并将该订单号传递给从数据库中检索数据的方法时，它向我显示数据库中没有这样的行，即使该条目已经在数据库。如果我手动硬编码表单2中的订单号就行了。

因此，一旦我在数据库中输入数据，如何从数据库中检索数据。

基本上，form1为用户提供订单号，表单2使用该订单号来获取数据。启动顺序是第一个表单1然后表单2.

要检索的代码

Form1 m = new Form1();
string number = m.orderNumber();
//  string number = "ORD1012013";

string InvSql = "SELECT  (Customer.[Title] + SPACE(2)  + Customer.[Customer's Name]) as CustomerName, Customer.[Customer's Ebayname], Customer.[Email Address], Customer.[Phone Number], (Customer.[Address 1] + SPACE(2)  +Customer.[Address 2] + SPACE(2)  + Customer.[City] + SPACE(2)  + Customer.[Post Code]+  SPACE(2)  + Customer.[Country]) as Address, Customer.[Item Purchased], Customer.[Purchased Date], Customer.[Total Price], Customer.[OrderNumber] FROM Customer WHERE Customer.[OrderNumber]= '" + number + "'";

OleDbConnection cnn = new OleDbConnection(connString);
OleDbCommand cmdOrder = new OleDbCommand(InvSql, cnn);

cnn.Open();

OleDbDataReader rdrOrder = cmdOrder.ExecuteReader();

rdrOrder.Read();

custName.Text = rdrOrder["CustomerName"].ToString();
ebayName.Text = rdrOrder["Customer's Ebayname"].ToString();
email.Text = rdrOrder["Email Address"].ToString();
phone.Text = rdrOrder["Phone Number"].ToString();
address.Text = rdrOrder["Address"].ToString();
item.Text = rdrOrder["Item Purchased"].ToString();
date.Text = Convert.ToString(Convert.ToDateTime(rdrOrder["Purchased Date"]));
price.Text = rdrOrder["Total Price"].ToString();
order.Text = rdrOrder["OrderNumber"].ToString();

rdrOrder.Close();
cnn.Close();

添加条目的代码

private void button1_Click(object sender, EventArgs e)
        {
            foreach (Control c in this.Controls)
            {
                if (c is MaskedTextBox)
                {
                    MaskedTextBox textBox = c as MaskedTextBox;
                    if (textBox.Text == string.Empty)
                    {

                        string result = MyMessageBox.ShowBox("Please Enter All Fields", "Warning");
                    }

                    else
                    {
                        SaveAllListItems();
                        this.Close();
                        PrintOrder m = new PrintOrder();
                        m.Show();

                    }
                }
            }

对于SaveAllListItems

 private void SaveAllListItems()
        {
            string listItems = string.Empty;
            foreach (var listBoxItem in listBox1.Items)
            {

                listItems += listBoxItem.ToString();

                if (listBox1.Items.IndexOf(listBoxItem) < listBox1.Items.Count - 1)
                {
                    listItems += ", ";
                }
            }

            InsertUser(maskedTextBox1.Text, comboBox1.Text, maskedTextBox2.Text, maskedTextBox3.Text, maskedTextBox4.Text, maskedTextBox5.Text,
                       maskedTextBox6.Text, maskedTextBox7.Text, maskedTextBox8.Text, maskedTextBox9.Text, listItems, DateTime.Now, maskedTextBox10.Text, orderNumber(), get_next_id());

;
        }

对于插入用户

public string InsertUser(string custName, string title, string cust,  string emailAddress, string phoneNumber, string address1, string address2, string city, string postCode, string country, string itemPurchased, DateTime datePurchased, string price,string orderNumber, int id)
{

    // Create connection objecte

    //string datePurchased = DateTime.Now.ToString("dd/MM/yyyy");


    int ix = 0;
    string rTurn = "";
    OleDbConnection oleConn = new OleDbConnection(connString);
    try
    {
        oleConn.Open();
        string sql = "INSERT INTO [Customer]([Customer's Ebayname], [Title],  [Customer's Name], [Email Address] ,[Phone Number], [Address 1], [Address 2], [City], [Post Code], [Country] , [Item Purchased], [Purchased Date], [Total Price], [OrderNumber], [NumGenerate])" +
                 "VALUES ( @custName, @title, @cust, @emailAddress, @phoneNumber, @address1, @address2, @city, @postCode, @country , @itemPurchased, @datePurchased, @price, @orderNumber, @id)";
        OleDbCommand oleComm = new OleDbCommand(sql, oleConn);

        oleComm.Parameters.Add("@custName", OleDbType.Char).Value = custName;
        oleComm.Parameters.Add("@title", OleDbType.Char).Value = title;
        oleComm.Parameters.Add("@cust", OleDbType.Char).Value = cust;
        oleComm.Parameters.Add("@emailAddress", OleDbType.Char).Value = emailAddress;
        oleComm.Parameters.Add("@phoneNumber", OleDbType.Char).Value = phoneNumber;
        oleComm.Parameters.Add("@address1", OleDbType.Char).Value = address1;
        oleComm.Parameters.Add("@address2", OleDbType.Char).Value = address2;
        oleComm.Parameters.Add("@city", OleDbType.Char).Value = city;
        oleComm.Parameters.Add("@postCode", OleDbType.Char).Value = postCode;
        oleComm.Parameters.Add("@country", OleDbType.Char).Value = country;
        oleComm.Parameters.Add("@itemPurchased", OleDbType.Char).Value = itemPurchased;
        oleComm.Parameters.Add("@datePurhcased", OleDbType.Date).Value = datePurchased;
        oleComm.Parameters.Add("@price", OleDbType.Char).Value = price;
        oleComm.Parameters.Add("@orderNumber", OleDbType.Char).Value = orderNumber;
        oleComm.Parameters.Add("@id", OleDbType.Integer).Value = id;



        ix = oleComm.ExecuteNonQuery();
        if (ix > 0)
            rTurn = "User Added";
        else
            rTurn = "Insert Failed";
    }
    catch (Exception ex)
    {
    }
    finally
    {
        oleConn.Close();
    }
    return rTurn;
    }

生成订单编号

  public string orderNumber()
        {
           string ord = "ORD" + get_next_id() + DateTime.Now.Year;
           return ord;
       }

Answer 1

在添加时再次调用m.orderNumber();，在检索时再次调用，并且在该方法中调用get_next_id()。因此，orderNumber正在从您保存的值中检索。（即保存订单＃1，检索订单＃2）

您应该将最后一个持久化的订单＃存储在静态属性中，或者直接将其传递给Form进行检索。

Answer 2

您检查了OrderNumber字段的排序规则吗？这定义了如何在SQL Server中存储/比较文本。要检查的另一件事是字母的情况。他们必须是大/小写吗？

在表单之间传递值并从数据库中检索数据

2 个答案: