Try This ->
static string Put_In_String()
{
SqlConnection myConnection = new SqlConnection();
myConnection.Open();
SqlCommand cmd = new SqlCommand();
cmd.CommandText = "select Query";
var result = cmd.ExecuteReader();
var myArray = new string[,] {};
var counter = 0;
while (result.Read())
{
myArray[counter, 0] = (string) result["First Column Name"];
myArray[counter, 1] = (string) result["Second Column Name"];
counter++;
}
result.Close();
myConnection.Close();
return myArray ;
}