Leçon 3 : Extraire une liste de champs pour la définition de rapport
Étant donné que chaque définition de rapport doit contenir une liste de champs qui représentent les données du rapport, vous devez créer cette liste à partir de votre requête.
Pour générer une liste de champs
- Remplacez le code de la méthode GenerateFieldsList() dans votre projet par le code suivant :
Public Sub GenerateFieldsList()
Dim command As SqlCommand
Dim reader As SqlDataReader
' Executing a query to retrieve a fields list for the report
command = m_connection.CreateCommand()
m_commandText = "SELECT Person.CountryRegion.Name AS CountryName, Person.StateProvince.Name AS StateProvince " + "FROM Person.StateProvince " + "INNER JOIN Person.CountryRegion ON Person.StateProvince.CountryRegionCode = Person.CountryRegion.CountryRegionCode " + "ORDER BY Person.CountryRegion.Name"
command.CommandText = m_commandText
' Execute and create a reader for the current command
reader = command.ExecuteReader(CommandBehavior.SchemaOnly)
' For each field in the resultset, add the name to an array list
m_fields = New ArrayList()
Dim i As Integer
For i = 0 To reader.FieldCount - 1
m_fields.Add(reader.GetName(i))
Next i
End Sub 'GenerateFieldsList
public void GenerateFieldsList()
{
SqlCommand command;
SqlDataReader reader;
// Executing a query to retrieve a fields list for the report
command = m_connection.CreateCommand();
m_commandText =
"SELECT Person.CountryRegion.Name AS CountryName, Person.StateProvince.Name AS StateProvince " +
"FROM Person.StateProvince " +
"INNER JOIN Person.CountryRegion ON Person.StateProvince.CountryRegionCode = Person.CountryRegion.CountryRegionCode " +
"ORDER BY Person.CountryRegion.Name";
command.CommandText = m_commandText;
// Execute and create a reader for the current command
reader = command.ExecuteReader(CommandBehavior.SchemaOnly);
// For each field in the resultset, add the name to an array list
m_fields = new ArrayList();
for (int i = 0; i <= reader.FieldCount - 1; i++)
{
m_fields.Add(reader.GetName(i));
}
}