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POKeep stuck at the reading the data from database
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  1. POKeep stuck at the reading the data from database
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    copied!<p>I would like to minus the data from the database with the value that I give when I run the program. Everything works, but I keep stuck at the <code>newVal</code>. I already did it like this, but the <code>newVal</code> keep appear <code>0</code> (because I declared <code>decimal newVal = 0</code>, but on this question, I just used <code>decimal newVal;</code>). Two more problems: if I move the <code>newVal = ...</code> to the top, it is useless, because one of the calculations in the <code>newVal</code> is reading data from the database (since I want database minus with the new value given when i run the program, required <code>dReader = cmd.ExecuteReader();</code>), but if I put the <code>newVal</code> at the bottom after reading data, it is useless as well, because I set the <code>Quantity = ?</code> and the value of <code>?</code> is <code>newVal..</code> Well, here is the code:</p> <pre><code>private void AddObjects(object sender, EventArgs e, Form theForm) { button1.Visible = true; textBoxQuantityContainer = new List&lt;NumericUpDown&gt;(); textBoxCodeContainer = new List&lt;NumericTextBox&gt;(); textBoxDescContainer = new List&lt;TextBox&gt;(); textBoxSubTotalContainer = new List&lt;TextBox&gt;(); textBoxTotalContainer = new List&lt;TextBox&gt;(); textBoxAllTotalContainer = new TextBox(); OleDbDataReader dReader; OleDbConnection conn = new OleDbConnection(connectionString); conn.Open(); OleDbCommand cmd = new OleDbCommand("SELECT [Code] FROM [Seranne]", conn); dReader = cmd.ExecuteReader(); AutoCompleteStringCollection codesCollection = new AutoCompleteStringCollection(); while (dReader.Read()) { string numString = dReader[0].ToString().PadLeft(4, '0'); codesCollection.Add(numString); } dReader.Close(); conn.Close(); if (firstForm.comboBox1.SelectedIndex == 0) { label1.Text = "Code:"; label1.Location = new Point(60, 125); label2.Text = "Welcome to the Selling System."; label2.Location = new Point(600, 30); label3.Text = "Quantity:"; label3.Location = new Point(155, 125); label4.Text = "Description:"; label4.Location = new Point(580, 125); label5.Text = "Sub Total on Rp:"; label5.Location = new Point(1020, 125); label6.Text = "Total on Rp:"; label6.Location = new Point(1210, 125); label7.Text = "Total on Rp:"; label7.Location = new Point(1080, 580); } else if (firstForm.comboBox1.SelectedIndex == 1) { label1.Text = "Kode:"; label1.Location = new Point(60, 125); label2.Text = "Selamat datang di Selling System."; label2.Location = new Point(600, 30); label3.Text = "Banyaknya:"; label3.Location = new Point(145, 125); label4.Text = "Keterangan:"; label4.Location = new Point(580, 125); label5.Text = "Sub Total di Rp:"; label5.Location = new Point(1020, 125); label6.Text = "Total di Rp:"; label6.Location = new Point(1210, 125); label7.Text = "Total di Rp:"; label7.Location = new Point(1080, 580); } //****TextBox for Code**** for (int y = 0; y &lt;= 16; y++) { textBoxCodeContainer.Add(new NumericTextBox()); textBoxCodeContainer[y].Size = new Size(100, 50); textBoxCodeContainer[y].Location = new Point(25, 150 + (y * 25)); textBoxCodeContainer[y].TextChanged += new System.EventHandler(this.textBox_TextChanged); textBoxCodeContainer[y].AutoCompleteMode = AutoCompleteMode.Suggest; textBoxCodeContainer[y].AutoCompleteSource = AutoCompleteSource.CustomSource; textBoxCodeContainer[y].AutoCompleteCustomSource = codesCollection; theForm.Controls.Add(textBoxCodeContainer[y]); } //****TextBox for Quantity**** for (int y = 0; y &lt;= 16; y++) { textBoxQuantityContainer.Add(new NumericUpDown()); textBoxQuantityContainer[y].Size = new Size(100, 50); textBoxQuantityContainer[y].Location = new Point(125, 150 + (y * 25)); textBoxQuantityContainer[y].TextChanged += new System.EventHandler(this.textBox_TextChanged); textBoxQuantityContainer[y].Maximum = 1000; theForm.Controls.Add(textBoxQuantityContainer[y]); } //****TextBox for Description**** for (int y = 0; y &lt;= 16; y++) { textBoxDescContainer.Add(new TextBox()); textBoxDescContainer[y].Size = new Size(750, 50); textBoxDescContainer[y].Location = new Point(225, 150 + (y * 25)); theForm.Controls.Add(textBoxDescContainer[y]); } //****TextBox for Sub Total**** for (int y = 0; y &lt;= 16; y++) { textBoxSubTotalContainer.Add(new TextBox()); textBoxSubTotalContainer[y].Size = new Size(175, 50); textBoxSubTotalContainer[y].Location = new Point(975, 150 + (y * 25)); theForm.Controls.Add(textBoxSubTotalContainer[y]); } //****TextBox for Total**** for (int y = 0; y &lt;= 16; y++) { textBoxTotalContainer.Add(new TextBox()); textBoxTotalContainer[y].Size = new Size(175, 50); textBoxTotalContainer[y].Location = new Point(1150, 150 + (y * 25)); textBoxTotalContainer[y].TextChanged += new System.EventHandler(this.textBox_TextChanged); theForm.Controls.Add(textBoxTotalContainer[y]); } //****TextBox for Total All**** textBoxAllTotalContainer.Size = new Size(175, 50); textBoxAllTotalContainer.Location = new Point(1150, 575); textBoxAllTotalContainer.TextChanged += new System.EventHandler(this.textBox_TextChanged); theForm.Controls.Add(textBoxAllTotalContainer); } private void UpdateDatas() { int codeValue = 0; int index = 0; string query = "SELECT [Quantity], [Description], [Price] FROM [Seranne] WHERE [Code] IN ("; OleDbConnection conn = new OleDbConnection(connectionString); conn.Open(); if (int.TryParse(this.textBoxCodeContainer[0].Text, out codeValue)) { query = query + codeValue.ToString(); } for (int i = 1; i &lt; 17; i++) { if (int.TryParse(this.textBoxCodeContainer[i].Text, out codeValue)) { query = query + "," + codeValue.ToString(); } } query = query + ")"; OleDbCommand cmd = new OleDbCommand(query, conn); OleDbDataReader dReader; dReader = cmd.ExecuteReader(); while (dReader.Read()) { if (textBoxCodeContainer[index].TextLength != 0) { this.textBoxQuantityContainer[index].Maximum = Convert.ToInt32(dReader["Quantity"].ToString()); this.textBoxDescContainer[index].Text = dReader["Description"].ToString(); this.textBoxSubTotalContainer[index].Text = dReader["Price"].ToString(); } index += 1; } dReader.Close(); conn.Close(); } private void UpdatePrice() { int totalPrice = 0; int quantity = 0; int price = 0; for (int i = 0; i &lt; 17; i++) { if (textBoxQuantityContainer[i].Value &gt; 0) { quantity = (int)textBoxQuantityContainer[i].Value; price = Convert.ToInt32(textBoxSubTotalContainer[i].Text); textBoxTotalContainer[i].Text = (quantity * price).ToString(); } else { textBoxSubTotalContainer[i].Text = ""; textBoxTotalContainer[i].Text = ""; } } for (int i = 0; i &lt; 17; i++) { if (textBoxTotalContainer[i].TextLength != 0) { totalPrice += Convert.ToInt32(textBoxTotalContainer[i].Text); } } textBoxAllTotalContainer.Text = totalPrice.ToString("n2"); } private void UpdateQuantity() { int index = 0; int codeValue = 0; decimal newVal; List&lt;int&gt; integers = new List&lt;int&gt;(); foreach (var tb in textBoxCodeContainer) { if (int.TryParse(tb.Text, out codeValue)) { integers.Add(codeValue); } } string command = "UPDATE [Seranne] SET [Quantity]=? WHERE [Code] IN(" + string.Join(", ", integers) + ")"; OleDbConnection conn = new OleDbConnection(connectionString); OleDbCommand cmd = new OleDbCommand(command, conn); cmd.Parameters.Add("Quantity", System.Data.OleDb.OleDbType.Integer); cmd.Parameters["Quantity"].Value = this.newVal.ToString(); OleDbDataReader dReader; conn.Open(); dReader = cmd.ExecuteReader(); while (dReader.Read()) { if (textBoxQuantityContainer[index].Value != 0) { newVal = (Convert.ToInt32(dReader["Quantity"].ToString()) - textBoxQuantityContainer[index].Value); int numberOfRows = cmd.ExecuteNonQuery(); } index += 1; } if (newVal == 0) { System.Media.SoundPlayer sounds = new System.Media.SoundPlayer(@"C:\Windows\Media\Windows Notify.wav"); sounds.Play(); MessageBox.Show("Cannot Update", "Error"); } else { System.Media.SoundPlayer sound = new System.Media.SoundPlayer(@"C:\Windows\Media\Windows Notify.wav"); sound.Play(); MessageBox.Show("Was Updated Successfully", "Success"); } dReader.Close(); conn.Close(); } private void textBox_TextChanged(object sender, EventArgs e) { UpdateDatas(); UpdatePrice(); } private void button1_Click(object sender, EventArgs e) { UpdateQuantity(); } </code></pre> <p>Thanks a bunch</p>
 

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