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POExecuteReader() making program exit Class
 

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    <p>I'm having a bit of trouble populating a listbox on a windows form from a table in sqlServer. The table is a single column of string values, and as I am ilkely to call this list of values many times throughout my application, I set it up as a Class, and in the default constructor I populate an ArrayList with the values from the SQL table, as follows:</p> <pre><code>class cCaseType { public ArrayList aValues = new ArrayList(); public cCaseType() { string strConnection = BuildConnectionString(); SqlConnection linkToDB = new SqlConnection(strConnection); string sqlText = "SELECT * FROM tblCaseTypes;"; SqlCommand sqlComm = new SqlCommand(sqlText, linkToDB); SqlDataReader sqlReader = sqlComm.ExecuteReader(); MessageBox.Show("Hi"); while (sqlReader.Read()) { aValues.Add(sqlReader["CaseType"].ToString()); } sqlReader.Close(); linkToDB.Close(); } public string BuildConnectionString() { cConnectionString cCS = new cConnectionString(); return cCS.strConnect; } } </code></pre> <p>Now I know the database connection is working becuase the same connection is used throughout the application. I know the SQL command text is corrext as when I execute it in SQL Management Studio it returns all the values in the table as expected. However, the program simply Exits at ExecuteReader() and so the ArrayList is never populated. </p> <p>I did wonder if the program was exiting because the 'while' loop was skipping due to an empty result from the reader, but its not even reaching the 'while' statement. I proved this by putting in the MessageBox and putting a breakpoint on it. The program never opens the messagebox proving that it is exiting the class on the ExecuteReader statement.</p> <p>What on earth am I doing wrong!</p> <p>As ever, thanks for any assistance.</p>
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    1. COHave you tried debuging?
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    2. COThe little advice - doing complex things (and loading data from db is "comlex") in constructor is not good practise. Extract your code into method.
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