簡體   English   中英

如何根據在使用SQLite填充的組合框中選擇的項目更改標簽的文本?

[英]How to change label's text depending on item selected on a combo box which is populated using SQLite?

我有一個按鈕,為TableLayoutPanel的列創建6個控件,6列是:訂單號,產品名稱( 組合框 ),當前數量( 標簽 ),購買數量,新數量和刪除行。

使用SQLite填充組合框。 對於Variants表,我有7列:[產品名稱],名稱,[序列號],[庫存現貨],[銷售前]。

我怎樣才能使“當前數量”下的標簽根據組合框中所選項目的[Stock On Hand]而變化?

在我當前的代碼中,每次我在組合框中選擇時,都會顯示“索引超出數組范圍”的錯誤。

用於創建動態組合框的代碼:

ComboBox cboItemName = new ComboBox
            {
                Name = "cboItemName" + rowIndex,
                Dock = DockStyle.Fill,
                DropDownStyle = ComboBoxStyle.DropDownList
            };
            cboItemName.SelectedIndexChanged += new EventHandler(cboItemName_SelectedIndexChanged);
            tblOrders.Controls.Add(FillComboBox(cboItemName));

組合框的事件處理程序的代碼:

 void cboItemName_SelectedIndexChanged(object sender, EventArgs e)
        {
            var cbo = (ComboBox)sender;
            string name = cbo.Name;
            string splittedString = new String(name.Where(Char.IsDigit).ToArray());;

            string labelName = "lblCurrentQuantity" + splittedString;
            string selectedIndex = cbo.SelectedIndex.ToString();
            string selectedItem = cbo.SelectedItem.ToString();

            Label tbx = tblOrders.Controls.Find(labelName, true).FirstOrDefault() as Label;
            EditLabelCurrentQuantity(tbx, selectedItem);
        }

最后,改變標簽文本的代碼:

private void EditLabelCurrentQuantity(Label label, string itemSelected)
        {
            auth = new Authentication();
            auth.getConnection();

            try
            {
                using (SQLiteConnection con = new SQLiteConnection(auth.connectionString))
                {

                    con.Open();

                    SQLiteCommand cmd = new SQLiteCommand();

                    cmd.CommandText = @"SELECT [Stock On Hand] FROM Variants WHERE Name='" + itemSelected + "'";
                    cmd.Connection = con;


                    SQLiteDataReader reader = cmd.ExecuteReader();
                    while (reader.Read())
                    {
                        string name = Convert.ToString(reader["[Stock On Hand]"]);
                    }

                    con.Close();
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
        }

我終於想通了,如果有人曾經遇到過我糟糕設計的事情,我已經通過添加以下內容解決了這個問題:

string name = Convert.ToString(reader[0]);
labelCategory.Text = name;

在:

SQLiteDataReader reader = cmd.ExecuteReader();
while (reader.Read())
{
    string name = Convert.ToString(reader["[Stock On Hand]"]);
}

暫無
暫無

聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.

 
粵ICP備18138465號  © 2020-2024 STACKOOM.COM