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I've got the following exception when I try to run the code below:

Hi Experts,

I've got the following exception when I try to run the code below:
ExecuteReader: CommandText property has not been initialized
The first time it runs without errors, the exception occours when I recall it.

conn = new SqlConnection(Constants.ConnectionDbSupporto);
string queryString = "SELECT COLUMN_NAME, DATA_TYPE, CHARACTER_MAXIMUM_LENGTH, NUMERIC_PRECISION, NUMERIC_SCALE FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME='" + nomeTab + "'";
SqlCommand sqlcmd = new SqlCommand(queryString, conn);

if (conn.State == ConnectionState.Closed)
conn.Open();
sqlcmd.CommandText = queryString;

sqlDr = sqlcmd.ExecuteReader();
while (sqlDr.Read())
{
... }

sqlDr.Close();

AndyAinscow

You mean like the following?

SomeFn()
{
conn = new SqlConnection(Constants.ConnectionDbSupporto);
                string queryString = "SELECT COLUMN_NAME, DATA_TYPE, CHARACTER_MAXIMUM_LENGTH, NUMERIC_PRECISION, NUMERIC_SCALE FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME='" + nomeTab + "'";
                SqlCommand sqlcmd = new SqlCommand(queryString, conn);


                if (conn.State == ConnectionState.Closed)
                    conn.Open();
                sqlcmd.CommandText = queryString;

                sqlDr = sqlcmd.ExecuteReader();
                while (sqlDr.Read())
                {
                    ...                }

                sqlDr.Close();
}

SomeOtherFn()
{
  SomeFn();  //OK
  SomeFn();  //Now fails with error
}

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theHollow

Hello
Try this instead:

SqlCommand sqlcmd = conn.CreateCommand();

:-)

dionisio_79

ASKER

I've tryed with the createcommand method but the result is still the same

The method is called in the ExportForm_load method which is the event handler for the form load event.
this.Load += new EventHandler(ExportForm_Load);

the second time, when I press a button, I recall the load method:

this.ExportForm_Load(this, new EventArgs());

AndyAinscow

BAD.

Have a function that performs this code.
Call the function from the Load event and from the button event.

ASKER CERTIFIED SOLUTION

AndyAinscow

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dionisio_79

ASKER

I've changed the code as you suggested but I've got the same result

SOLUTION