70-523 Real Exam Prep DEMO

Question 17: You use Microsoft Visual Studio 2010 and Microsoft .NET Framework 4 to create an application. You
are creating the data layer of the application. You write the following code segment. (Line numbers are
included for reference only.)
01 public static SqlDataReader GetDataReader(string sql){
02 SqlDataReader dr = null;
03
04 return dr;
05 }
You need to ensure that the following requirements are met:
Ð The SqlDataReader returned by the GetDataReader method can be used to retrieve rows from the
database.
Ð SQL connections opened within the GetDataReader method will close when the SqlDataReader is
closed.
Which code segment should you insert at line 03?
A. using (SqlConnection cnn = new SqlConnection(strCnn)) {
try {
SqlCommand cmd = new SqlCommand(sql, cnn);
cnn.Open();
dr = cmd.ExecuteReader();
}
catch {
throw;
}
}
B. SqlConnection cnn = new SqlConnection(strCnn);
SqlCommand cmd = new SqlCommand(sql, cnn);
cnn.Open();
try {
dr = cmd.ExecuteReader();
}
finally {
cnn.Close();
}
C. SqlConnection cnn = new SqlConnection(strCnn);
SqlCommand cmd = new SqlCommand(sql, cnn);
cnn.Open();
try {
dr = cmd.ExecuteReader();
cnn.Close();
}
catch {
throw;
}
D. SqlConnection cnn = new SqlConnection(strCnn);
SqlCommand cmd = new SqlCommand(sql, cnn);
cnn.Open();
try {
dr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
}
catch {
cnn.Close();
throw;
}
Correct Answer: D