Develop Reference

Autocomplete comboBox that checks items in its list are entered

Is there a way to check when an item is entered in a comboBox, is only one in which is actually in the list? To explain further, if anything outside the list is selected it won't accept that input. I've looked within stackoverflow but the only solution am seeing is that of changing my comboBox style to a dropdown list style. The problem with this is that there are more than a hundred records to select from so the autocomplete on the comboBox is absolutely necessary to filter these out by the user input entered.
Updated(declared matched globally):
private void comboBox3_TextChanged(object sender, EventArgs e)
{
ComboBox c = ((ComboBox)sender);
string[] items = c.Items.OfType<string>().ToArray();
matched = items.Any(i => i == c.Text.Trim().ToLower());
}
and this is where it executes:
private void button5_Click(object sender, EventArgs e)
{
if (matched==false)
{
MessageBox.Show("Value in Carimed Items does not exist");
}else
{
if (string.IsNullOrEmpty(comboBox5.Text))
{
MessageBox.Show("Please select output file to be written to!");
}
else
{
// int current = 0;
if (comboBox1.Text.Trim() == string.Empty)
{
MessageBox.Show("All fields must be filled in before saving!");
}
else
{
// StringBuilder csvconten = new StringBuilder();
// csvconten.AppendFormat("{0},{1},{2},{3},{4},{5}\r\n", comboBox2.Text, textBox5.Text, textBox2.Text, comboBox3.Text, textBox3.Text, comboBox1.Text);
// string csvpath = "cross_check.csv";
// File.AppendAllText(csvpath, csvconten.ToString());
string connectionString3 = "Data Source=LPMSW09000012JD\\SQLEXPRESS;Initial Catalog=Pharmacy_Output_File;Integrated Security=True";
string query3 = "INSERT INTO dbo.[" + comboBox5.Text + "] VALUES('" + comboBox2.Text + "','" + textBox5.Text.Replace("'", "''") + "','" + textBox7.Text.Replace("'", "''") + "','" + textBox2.Text.Replace("'", "''") + "','" + comboBox3.Text.Replace("'", "''") + "','" + textBox3.Text + "','" + comboBox1.Text + "');";
using (SqlConnection connection = new SqlConnection(connectionString3))
{
SqlCommand command = new SqlCommand(query3, connection);
command.Connection.Open();
command.ExecuteNonQuery();
command.Connection.Close();
}
// textBox1.Clear();
// textBox3.Clear();
// comboBox3.ResetText();
textBox2.Clear();
textBox3.Clear();
comboBox3.ResetText();
comboBox1.ResetText();
}
string connectionString2 = "Data Source=LPMSW09000012JD\\SQLEXPRESS;Initial Catalog=Pharmacies;Integrated Security=True";
string query2 = "UPDATE Liguanea_Lane2 SET Progress= '1' where code = '" + comboBox2.Text + "'; ";
using (SqlConnection connection = new SqlConnection(connectionString2))
{
SqlCommand command = new SqlCommand(query2, connection);
command.Connection.Open();
command.ExecuteNonQuery();
}
//this.liguanea_ProgressTableAdapter1.Fill(this.pharmaciesDataSet7.Liguanea_Progress);
comboBox2.SelectedIndex = comboBox2.SelectedIndex + 1;
//current = liguaneaLane2BindingSource.Position;
//this.liguanea_Lane2TableAdapter.Fill(this.pharmaciesDataSet3.Liguanea_Lane2);
refreshDataGrid2();
if (dataGridView1.CurrentRow != null)
{
dataGridView1.CurrentCell =
dataGridView1
.Rows[Math.Min(dataGridView1.CurrentRow.Index + 1, dataGridView1.Rows.Count - 1)]
.Cells[dataGridView1.CurrentCell.ColumnIndex];
// liguaneaLane2BindingSource.Position = Math.Min(current + 1, liguaneaLane2BindingSource.Count - 1);
}
}
}
}

You can Use the TextChanged Event of the ComboBox to See if the enter text exsists in you list:
private void comboBox1_TextChanged(object sender, EventArgs e)
{
ComboBox c = ((ComboBox)sender);
string[] items = c.Items.OfType<string>().ToArray();
bool matched = items.Any(i => i == c.Text.Trim().ToLower());
}
You can declare the matched bool globally in the form that TextChanged event would assign its value then you can use it in other Methods like:
void Button_Click(object sender, e EventArgs){
if(matched)
{
//do something
} else{
// show an error message
}
}

exception of duplicate key in my code

I have a Form that contains an "Add" button and a textBox, which is used to add information to a database table.
I need to check if the code entered in the TextBox is available before I can insert it.
My problem is that I get errors, as it attempts to add a "duplicate primary key" and I'm unsure of the source of error.
Below is the code I currently have:
private void button2_Click(object sender, EventArgs e)
{
SqlConnection connection1 = new SqlConnection(connectionString);
connection1.Open();
String reqt1="select numero_cpte from compte where numero_cpte="+textBox1.Text+";";
SqlCommand sql1 = new SqlCommand(reqt1, connection1);
int d = int.Parse(textBox1.Text);
int dd = Convert.ToInt32(sql1.ExecuteScalar());
if(d == dd)
{
int o1 = sql1.ExecuteNonQuery();
MessageBox.Show("this account is not valide!!","Fiche ");
connection1.Close();
}
if (String.IsNullOrEmpty(textBox1.Text) == true)
{
MessageBox.Show("You should insert the code!!","Fiche",
MessageBoxButtons.OK,MessageBoxIcon.Information);
}
else
{
SqlConnection connection = new SqlConnection(connectionString);
connection.Open();
SqlCommand sql = new
SqlCommand("insert into compte values(" + textBox1.Text + ",'" +
textBox2.Text + "','" + type_cpteComboBox.SelectedItem.ToString() +
"','" + textBox2.Text + "','" + comboBox1.SelectedItem.ToString() +
"'," + comboBox2.SelectedItem.ToString() + ",'" +
checkBox1.Checked.ToString() + "','" + checkBox2.Checked.ToString() +
"','" +textBox5.Text+ "','" +textBox6.Text+ "');", connection);
int o = sql.ExecuteNonQuery();
MessageBox.Show(o + "Success of add","Fiche");
connection.Close();
textBox1.Text = "";
textBox2.Text = "";
}
This is the error I see:
The insert command works perfectly, but When I try to test if the code that I'am going to add in the base exists or not (by typing a code that I know exists), I get this exception.

It looks like your code drops down into the add code even if you have discovered that your number is a duplicate. Try adding "return;" after you close the connection.
MessageBox.Show("Ce compte existe.Veuillez sasir un numéro de compte valide!!", "Fiche Comptes");
connection1.Close();
return;

private object ExecuteScalar(string sql)
{
using (SqlConnection connection1 = new SqlConnection(connectionString))
{
connection1.Open();
SqlCommand sql1 = new SqlCommand(sql, connection1);
return sql1.ExecuteScalar();
}
}
The advantage of this is that you always know that your connection will be closed when you are done. Even if you are only going to be calling this method once, it improves readability and is therefore helpful.

incorrect syntax near ');

I have an error with my code.
Code execution directly flows to the catch block and says: incorrect syntax near ');
I want to save a file in the database and call it again.
public partial class newsrv : System.Web.UI.Page{
string dir = "C://fileup//";
protected void Page_Load(object sender, EventArgs e){
if (!Directory.Exists(dir)){
Directory.CreateDirectory(dir);
}
}
protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e){
}
protected void Button1_Click(object sender, EventArgs e){
SqlConnection con = new SqlConnection("Data Source=.\\SQLEXPRESS;AttachDbFilename=|DataDirectory|DB.mdf;Integrated Security=True;User Instance=True");
string fname = FileUpload1.PostedFile.FileName;
try{
SqlCommand cmd = new SqlCommand("INSERT INTO OrderNum (SrviceType, Msg,[File]) VALUES ('" + DropDownList1.SelectedItem.Text + "','" + TextBox1.Text + "' ,'" + FileUpload1.PostedFile.FileName + "') );", con);
con.Open();
try {
int res = cmd.ExecuteNonQuery();
if (res > 0){
System.Windows.Forms.MessageBox.Show("success");
}
Label2.Text = TextBox1.Text;
FileUpload1.SaveAs(dir + fname);
Label1.Text = " file name uploaded succ ";
FileUpload1.Visible = true;
}catch (Exception ex){
System.Windows.Forms.MessageBox.Show(ex.Message);
}
}catch{
Label1.Text = " file name not uploaded ";
FileUpload1.Visible = false;
con.Close();
}finally{
con.Close();
}
}
protected void TextBox1_TextChanged(object sender, EventArgs e){
}
}

It looks like you have an extra ); at the end of the SQL statement...
... + TextBox1.Text + "' ,'" + FileUpload1.PostedFile.FileName + "') );", con);
^^
remove these

I think you should get rid of ); in:
"') );",
Also, consider using placeholders for better security.

Your SQLCommand is invalid. It should be:
SqlCommand cmd = new SqlCommand("INSERT INTO OrderNum (SrviceType, Msg,[File]) VALUES ('" + DropDownList1.SelectedItem.Text + "','" + TextBox1.Text + "' ,'" + FileUpload1.PostedFile.FileName + "')", con);
E.G. Remove the extra ); at the end of the statement.

Don't put ); at the end of the query. And for an easy compresion use this syntax:
SqlCommand cmd=new SqlCommand(String.Format(#"INSERT INTO OrderNum (SrviceType, Msg,[File]) VALUES ('{0},{1},{2}')",DropDownList1.SelectedItem.Text, TextBox1.Text,FileUpload1.PostedFile.FileName),con);
For better understanding change the name of the obj in something that remember what you want do with this.
Example if you have a textbox that required the username call the textbox txtUserName or txtNickName

How to not catch the old data in page load

I trying to update my profile but it keep catching the old data when it update. What can be done to solve this problem. Please help me out on this problem thanks!
protected void Page_Load(object sender, EventArgs e)
{
String nric = (String)Session["nric"];
SqlConnection con = new SqlConnection("Data Source = localhost; Initial Catalog = MajorProject; Integrated Security= SSPI");
con.Open();
SqlCommand cm = new SqlCommand("Select * from MemberAccount where nric = '" + nric + "'", con);
SqlDataReader dr;
dr = cm.ExecuteReader();
if (dr.Read())
{
txtFullName.Text = dr["fullname"].ToString();
txtAddress.Text = dr["address"].ToString();
txtContact.Text = dr["contact"].ToString();
txtEmail.Text = dr["email"].ToString();
}
con.Close();
}
protected void btnUpdate_Click(object sender, EventArgs e)
{
String nric = (String)Session["nric"];
if (txtContact.Text.Equals("") || txtEmail.Text.Equals(""))
{
lblMessage.Text = "Do not leave blank fill to update your profile!";
}
else
{
string strQuery = "Update MemberAccount Set address = '" + txtAddress.Text + "', contact = '" + txtContact.Text + "', email = '" + txtEmail.Text + "' Where nric = '" + nric + "'";
SqlCommand cmd = new SqlCommand(strQuery);
InsertUpdateData(cmd);
lblMessage.ForeColor = System.Drawing.Color.Green;
lblMessage.Text = "Profile Updated.";
}
}

Sounds like you could just apply an IsPostBack check in your Page_Load method. http://msdn.microsoft.com/en-us/library/system.web.ui.page.ispostback.aspx
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack) {
// Load data
}
}
Note: your code looks susceptible to SQL injection.

Data gets Truncated from database

I am designing a Window based application in C# using VS2010 and SqlServer2008-r2. I am
using a service Based Database(.mdf),in it there is a table having four fields, if i Store
data in the table and close the application and re-run the application the data gets Lost.
Why so and how to get rid of it.
I am Using Following routine for saving
private void Save(object sender, EventArgs e)
{
Program.connection.Close();
bool k = srchpreventry();
try
{
if (k)
{
string query = " update orderform set Enrolment_Expected = " + textBox2.Text + ", Stock_on_Hand=" + textBox3.Text + ", Number_Required = "+ textBox4.Text + " where Name = '" + textBox1.Text + "';";
SqlCommand cmd = new SqlCommand(query, Program.connection);
cmd.ExecuteNonQuery();
Program.connection.Close();
}
else
{
// Program.connection.Open();
string query = "insert into orderform(Name,Enrolment_Expected,Stock_on_Hand,Number_Required) values('" + textBox1.Text + "', '" + textBox2.Text + "', ' " + textBox3.Text + "',' " + textBox4.Text + "')";
SqlCommand cmd = new SqlCommand(query, Program.connection);
cmd.ExecuteNonQuery();
Program.connection.Close();
}
}
catch (Exception ae)
{
string str = ae.ToString();
MessageBox.Show(str);
}
finally
{
textBox1.Text = "";
textBox2.Text = "";
textBox3.Text = "";
textBox4.Text = "";
textBox1.Enabled = false;
textBox2.Enabled = false;
textBox3.Enabled = false;
textBox4.Enabled = false;
Program.connection.Close();
}
}
public bool srchpreventry()
{
Program.connection.Open();
string query = " Select name from orderform where Name = '" + textBox1.Text + "';";
SqlCommand cmd = new SqlCommand(query, Program.connection);
SqlDataReader dtr = cmd.ExecuteReader();
if (dtr.Read() == true)
{
dtr.Close();
return true;
}
else
{
dtr.Close();
return false;
}
}
private void textBox1_TextChanged(object sender, EventArgs e)
{
Program.connection.Close();
Program.connection.Open();
string query = " Select * from orderform where Name = '" + textBox1.Text + "';";
SqlCommand cmd = new SqlCommand(query, Program.connection);
SqlDataReader dtr = cmd.ExecuteReader();
if (dtr.Read() == true)
{
textBox2.Text = dtr[1].ToString();
textBox3.Text = dtr[2].ToString();//GetString(2);
textBox4.Text = dtr[3].ToString();
}
else
{
textBox2.Text = "";
textBox3.Text = "";
textBox4.Text = "";
}
}
public static SqlConnection connection = null;
static string appath = Library_Records.Program.app_path;
string connectionstring = string.Format(#"Data Source=.\SQLEXPRESS;AttachDbFilename={0};Integrated Security=True;User Instance=True", appath);
static string dbfiles = null;
internal static string app_path
{
get { return dbfiles = "|Datadirectory|\\records.mdf"; }
}
/*******************datagrid code********************/
Program.connection.Open();
string query = "select * from orderform";
SqlDataAdapter MyDA = new SqlDataAdapter();
MyDA.SelectCommand = new SqlCommand(query, Program.connection);
DataTable table = new DataTable();
MyDA.Fill(table);
BindingSource bSource = new BindingSource();
bSource.DataSource = table;
dataGridView1.DataSource = bSource;

Check to see if you can increase the characters allowed in the column for example nvarchar(max) cause now it could be nvarchar(200) - this is just an example

In Visual Studio?
You are not by chane having VIsual Studio load the same empty database again every time you start debug?
and close the application and re-run the application the data gets Lost.
Either someone ignores errors that get thrown on insert, does not commit a transaction or tvisal studio just ocpies the same rdatabase template into the directory every time you start.

I strongly (emphasis on strongly) suggest that you start using stored procedures (either in code or in the database), but besides that.. you don't start a transaction or something similar?
Or post the Program.Connection class code into the question.