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ASP.NET getting data from SQL Server

I am trying to get the name of the employee from the database and fill it in the textbox for the respective employee id.
I tried this code but nothing is happening on the page. It just reloads and the textbox (name) is left blank only.
SqlConnection con = new SqlConnection(#"Data Source=DESKTOP-0FUUV7B\SQLEXPRESS;Initial Catalog=EmployeeDetails;Integrated Security=True");
con.Open();
           
SqlCommand cmd = new SqlCommand("select * from ProfessionalDetails where EmpId='"+EmployeeId.Text+"'", con);
          
SqlDataReader da = cmd.ExecuteReader();
while (da.Read())
{
    Name.Text = da.GetValue(1).ToString();
}
            
con.Close();

Better solution is to execute the sql statement through Parameterized value.
The details of that process is given below:
using (SqlConnection con = new SqlConnection(live_connectionString))
{
using (SqlCommand cmd = new SqlCommand("Query", con))
{
con.Open();
cmd.CommandType = CommandType.Text;
cmd.Parameters.AddWithValue("#EmpId", employeeId);
SqlDataAdapter da = new SqlDataAdapter();
da.SelectCommand = cmd;
var ds = new DataSet();
da.Fill(ds);
string? name = ds.Tables[0].Rows[1]["Variable name"].ToString();
Name.Text =name;
};
}
}

As mentioned above in comments, you have lot of issues.
you should use using with the connection to dispose of them.
You should use parameterized queries to avoid SQL injection.
Put your code in try catch so that you can easily identify the root cause of the issue.
Define the connection string in config file three than defining in the c# code.
You don’t need to select all the columns. And please avoid select * in the query, instead just write your column name, as you want to select only one column here.
You can use ExecuteScalar, it’s used when you are expecting single value.
And first make sure that textbox has the expected value when you are calling this query.

As noted, use paramters, and BETTER use STRONG typed paramters.
And no need to use a dataset, this is a single table - so use a datatable.
thus:
string strSQL =
#"select * from ProfessionalDetails where EmpId= #ID";
using (SqlConnection con = new SqlConnection(Properties.Settings.Default.TEST4))
{
using (SqlCommand cmd = new SqlCommand(strSQL, con))
{
con.Open();
cmd.Parameters.Add("#ID", SqlDbType.Int).Value = EmployeeID.Text;
DataTable rstData = new DataTable();
rstData.Load(cmd.ExecuteReader());
if (rstData.Rows.Count > 0)
Name.Text = rstData.Rows[0]["Name"].ToString();
}
}

SQLConnection bringing data to TextBox

I know this looks really simple but i've been looking for an answer for hours with no luck.
I want to fill my row values into a bunch of textboxes. How can I specify that [CompanyName] is going to be used by the companyName textbox? Please keep it as simple as possible (beginner level).
string customerUniqueID = "test";
string constr = ConfigurationManager.ConnectionStrings["SQLConnection"].ToString(); // connection string
SqlConnection con = new SqlConnection(constr);
con.Open();
SqlCommand com = new SqlCommand("SELECT * FROM [Customers] WHERE [UniqueID] = #UniqueID", con); // table name
com.Parameters.Add("#UniqueID", SqlDbType.Int);
com.Parameters["#UniqueID"].Value = customerUniqueID;
SqlDataAdapter da = new SqlDataAdapter(com);
DataSet ds = new DataSet();
companyName.Text = ?????????

string customerUniqueID = "test";
string constr = ConfigurationManager.ConnectionStrings["SQLConnection"].ToString(); // connection string
SqlConnection con = new SqlConnection(constr);
con.Open();
SqlCommand com = new SqlCommand("SELECT * FROM [Customers] WHERE [UniqueID] = #UniqueID", con); // table name
com.Parameters.Add("#UniqueID", SqlDbType.Int);
com.Parameters["#UniqueID"].Value = customerUniqueID;
SqlDataAdapter da = new SqlDataAdapter(com);
DataSet ds = new DataSet();
da.Fill(ds, "Customers");
companyName.Text = ds.Tables[0].Rows[0]["CompanyName"].ToString();

I will recommend some changes in your code:
Your sql query returning result from one set, so you can use DataTabe instead of DataSet.
To fill results from DB to your DataTable you can use SqlAdapter.Fill() method.
Use Field() generic method (more examples of Field()) to get values from your DataTable.
Use using blocks for disposable objects, or at least make sure you've closed them after.
There is no need of con.Open() to open connection when using Fill() method, because from MSDN:
The Fill method implicitly opens the Connection that the DataAdapter is using if it finds that the connection is not already open. If Fill opened the connection, it will also close the connection when Fill is finished. This can simplify your code when dealing with a single operation such as a Fill or an Update.
string customerUniqueID = "test";
string constr = ConfigurationManager.ConnectionStrings["SQLConnection"].ToString(); // connection string
using(SqlConnection con = new SqlConnection(constr))
{
SqlCommand com = con.CreateCommand();
com.CommandText = "SELECT * FROM [Customers] WHERE [UniqueID] = #UniqueID";
com.Parameters.Add("#UniqueID", SqlDbType.Int);
com.Parameters["#UniqueID"].Value = customerUniqueID;
using(SqlDataAdapter da = new SqlDataAdapter(com))
{
DataTable dt = new DataTable();
da.Fill(dt);
companyName.Text = dt.Rows[0].Field<string>("CompanyName");
}
}
Please feel free to comment, if I missed something.

Procedure or function sp_select_companydetails has too many arguments specified

I am really get depressed about this error all function code is correct but still its giving me the error, I am trying to select information from SQL Server database.
Stored procedure:
create procedure sp_select_companydetails
#id varchar(5)
as
begin
select company_name, company_address
from CompanyDetails
end
C# Code:
2) On Form button click event
string id = "1";
cmd.CommandType = CommandType.StoredProcedure;
cmd.CommandText = "sp_select_companydetails";
cmd.Parameters.Add("#id", id);
FillDataset();
In class
public DataSet FillDataset()
{
try
{
using (cmd)
{
DataSet ds = new DataSet();
cmd.Connection = con;
SqlDataAdapter da = new SqlDataAdapter(cmd);
da.Fill(ds);
cmd.Parameters.Clear();
return ds;
}
}
catch (Exception)
{
throw;
}
}
When I click on form button I get this error:
Procedure or function sp_select_companydetails has too many arguments specified.
Suggest me good solution
Thank you in advance

Instead of using a global SqlCommand, create it as new everytime you need it. This is a recommended approach when you deal with disposable objects
using (SqlConnection con = new SqlConnection(GetConnectionString())
using (SqlCommand myCmd = new SqlCommand("sp_select_companydetails", con))
{
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Add("#id", SqlDbType.VarChar).Value = "1";
DataSet ds = new DataSet();
SqlDataAdapter da = new SqlDataAdapter(cmd);
da.Fill(ds);
return ds;
}
By the way, we cannot see how do you create the SqlConnection, but it seems that you have another disposable object kept at the global level. This is particular nasty with an SqlConnection because this object keeps references to system wide resources both on client and on server. Do not create global connection objects, just create a global method that returns the current connectionstring to use in creation of the local SqlConnection (the GetConnectionString() in my example above). If you think that this is a performance killer I suggest you to read about the concept of connection pooling

How to use DataAdapter to call a stored procedure in C# with variable parameters

I am calling the following code in C# to fill a dataAdapter with a given stored procedure "sp1_name". The problem is that I want to call different stored procedures with different parameters. (All SP's do a SELECT)
Let's suppose that my stored procedure name is "SP_SOMESP", then everything works fine.
Let's suppose that my stored procedure name is "SP_SOMESP #Month= 10, #Year = 2010", then it doesn't work. It throws an exception that cannot find this stored procedure.
Any solutions?
Thanks!
//First Connection - SP1
using (SqlConnection con = new SqlConnection(conStr))
{
using (SqlCommand cmd = new SqlCommand(sp1_name, con)) //sp1_name = NAME + PARAMETERS
{
cmd.CommandTimeout = 3600;
cmd.CommandType = CommandType.StoredProcedure;
using (SqlDataAdapter dataAdapter = new SqlDataAdapter(cmd))
{
dataAdapter.Fill(results2);
}
}
}

First Issue:
Parameters in a stored procedure shouldn't be included along with its name
Second Issue:
Having a space in names of stored procedure isn't a good practice.
And for code behind
using(SqlConnection con = new SqlConnection("Your Connection String Here"))
{
SqlCommand cmd = new SqlCommand("sp_SomeName", con);
cmd.CommandType = CommandType.StoredProcedure;
//the 2 codes after this comment is where you assign value to the parameters you
//have on your stored procedure from SQL
cmd.Parameters.Add("#MONTH", SqlDbType.VarChar).Value = "someValue";
cmd.Parameters.Add("#YEAR", SqlDbType.VarChar).Value = "SomeYear";
SqlDataAdapter da = new SqlDataAdapter(cmd);
SqlDataSet ds = new SqlDataSet();
da.Fill(ds); //this is where you put values you get from the Select command to a
//dataset named ds, reason for this is for you to fetch the value from DB to code behind
foreach(DataRow dr in ds.Tables[0].Rows) // this is where you run through the dataset and get values you want from it.
{
someTextBox.Text = dr["Month"].ToString(); //you should probably know this code
}
}

You have to add in the parameters programmatically, see SqlCommand.Parameters.
It would be something like
cmd.Parameters.AddWithValue("#Month", 10);
cmd.Parameters.AddWithValue("#Year", 2010);
This would be after the command is declared and before it is executed.
If you find that you need to delcare the data type, then try it this way
cmd.Parameters.Add("#Month", SqlDbType.Int).Value = 10;

Check this,
using (SQLCommand cmd = new SQLCommand())
{
cmd.CommandText = "SP_SOMESP";
cmd.Parameters.Add("#Month", 10);
cmd.Parameters.Add("#Year", 2010);
cmd.CommandTimeout = 3600;
cmd.CommandType = CommandType.StoredProcedure;
cmd.Connection = con;
}
using (SqlDataAdapter dataAdapter = new SqlDataAdapter(cmd))
{
dataAdapter.SelectCommand = cmd;
dataAdapter.Fill(results2);
}

Parameter not changing in OleDbCommand

This is a simple search page (search.aspx?title=Hello) and I want to query the db for like matches. According to the microsoft docs (http://msdn.microsoft.com/en-us/library/system.data.oledb.oledbparameter.aspx see: Remarks) this is the correct way to do it, but the parameter (?) never gets set to the value of the query string.
string sqlcmd = "SELECT * FROM TableName WHERE Title LIKE ?";
OleDbCommand command = new OleDbCommand(sqlcmd, sqlcon);
OleDbParameter p1 = new OleDbParameter("#p1", OleDbType.WChar);
p1.Value = Request.QueryString["title"];
OleDbDataAdapter da = new OleDbDataAdapter(command);
da.SelectCommand.Parameters.Add(p1);
DataTable dt = new DataTable();
da.Fill(dt);
The parameter never changes to what the query string was, it just executes the query
SELECT * FROM Table WHERE Title LIKE ?

Could you try the following:
"SELECT * FROM Table WHERE Title LIKE #p1"
I think that is the convention when using parameters in ADO.Net command text.

Here is my solution, you need to have single quotes around the question mark for the SQL to work. Complete solution:
sqlcon.Open();
string sqlcmd = "SELECT * FROM TableName WHERE Title LIKE '%?%'";
OleDbCommand command = new OleDbCommand(sqlcmd, sqlcon);
command.Parameters.Add(new OleDbParameter("p1", Request.QueryString["Title"]));
OleDbDataAdapter da = new OleDbDataAdapter(command);
DataTable dt = new DataTable();
da.Fill(dt);