Get SQL data And show it in a text box?

Question

In the last few days I am trying to get data from my SQL table and get it into my textbox.

The table name : "check".

The code I am using :

SqlDataReader myReader = null;

connection = new SqlConnection(System.Configuration.ConfigurationManager
                    .ConnectionStrings["ConnectionString"].ConnectionString);
connection.Open();

var command = new SqlCommand("SELECT * FROM [check]", connection);
myReader = command.ExecuteReader();
while (myReader.Read())
{
    TextBox1.Text = myReader.ToString();
}
connection.Close();

I am getting nothing as a result. Anyone know why? Maybe I am not calling the SQL correctly?

Solution 1

using (var connection = new SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString))
using (var command = connection.CreateCommand())
{
    command.CommandText = "SELECT ColumnName FROM [check]";
    connection.Open();
    using (var reader = command.ExecuteReader())
    {
        while (reader.Read())
            TextBox1.Text = reader["ColumnName"].ToString();
    }
}

Some comments:

• don't use *, specify only those fields that you need
• use using - less code, guaranteed disposal
• I assume this is a test program, otherwise it does not make sense to reset Text to a in the loop

Solution 2

 TextBox1.Text = myReader["fieldname"].ToString();

also I think you can change while with if because for every row from your table you'll overwrite textbox text!

Solution 3

Try this:

TextBox1.AppendText(myReader["columnname"].ToString());

Comments

[Alon M]

i have changed the code to : protected void Button1_Click(object sender, EventArgs e) { SqlDataReader myReader = null; using (var connection = new SqlConnection(System.Configuration.ConfigurationManager.Conn‌​ectionStrings["Conne‌​ctionString"].Connec‌​tionString)) using (var command = connection.CreateCommand()) { command.CommandText = "SELECT ItemNow FROM [check]"; connection.Open(); while (myReader.Read()) TextBox1.Text = TextBox1.Text + myReader["ItemNow"].ToString(); } still not working :( thanks all !

[Hasan Fahim]

@user796862. You've commented on a different answer. Anyways use AppendText as I specified.

[marc_s]

+1 for your comments - every C# database developer should follow those - always!

[Hasan Fahim]

@user796862. I don't see myReader = command.ExecuteReader(); in your last comment. Maybe this is causing issue. Anyways did you check the text present in myReader["ItemNow"].ToString() in QuickWatch? What error are you getting? Debug the code and identify the line on which you are getting error.

[Alon M]

i am done debug, nothing happnd. its saying "All ok." no errors. but the textbox is empty. i done like this :myReader = command.ExecuteReader(); command.CommandText = "SELECT [ItemNow] FROM [check]"; connection.Open(); while (myReader.Read()) TextBox1.Text = TextBox1.Text +myReader["ItemNow"].ToString();

[Hasan Fahim]

@Alon M. You need to do this: TextBox1.AppendText(myReader["ItemNow"].ToString()); Also add the value of myReader["ItemNow"].ToString() in Watch and set a break point inside the while loop where text is appended, to check what text is being appended.

[Alon M]

Thanks.. Its working. Ty All :).(i have done some errors in the db it self, this is the reseon it didnt work) thanks all again.