I am busy with an e-commerce web application using visual studio 2005 and IIS 7
I got this error
System.TypeInitializationException was unhandled by user code
Message="The type initializer for 'ShopConfiguration' threw an exception."
Source="App_Code.r-ihwy-d"
TypeName="ShopConfiguration"
StackTrace:
at ShopConfiguration.get_DbProviderName()
at GenericDataAccess.CreateCommand() in c:\inetpub\wwwroot\Beadafrican\App_Code\GenericDataAccess.cs:line 63
at CatalogAccess.GetDepartments() in c:\inetpub\wwwroot\Beadafrican\App_Code\CatalogAccess.cs:line 28
at UserControls_DepartmentsList.Page_Load(Object sender, EventArgs e) in c:\inetpub\wwwroot\Beadafrican\UserControls\DepartmentsList.ascx.cs:line 22
at System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o, Object t, EventArgs e)
at System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e)
at System.Web.UI.Control.OnLoad(EventArgs e)
at System.Web.UI.Control.LoadRecursive()
at System.Web.UI.Control.LoadRecursive()
at System.Web.UI.Control.LoadRecursive()
at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)
If I look at the code it refers to I dont see what is wrong? Here is the code if anyone can please assist it would be great!
GenericDataAccess.cs:
public static class GenericDataAccess { //static constructor static GenericDataAccess() { // // TODO: Add constructor logic here // }
//execute a command and returns the result as a DataTable Object
public static DataTable ExecuteSelectCommand(DbCommand command)
{
//The DataTable to be returned
DataTable table;
//Execute the command making sure the connection gets closed in the end
try
{
//open the data connection
command.Connection.Open();
//Execute the command and save the results in a DataTable
DbDataReader reader = command.ExecuteReader();
table = new DataTable();
table.Load(reader);
//Close the reader
reader.Close();
}
catch (Exception ex)
{
Utilities.LogError(ex);
throw ex;
}
finally
{
//Close the connection
command.Connection.Close();
}
return table;
}
//creates and prepares a new DbCommand object on a new connection
public static DbCommand CreateCommand()
{
//Obtain the database provider name
string dataProviderName = ShopConfiguration.DbProviderName;
//Obtain the database connection string
string connectionString = ShopConfiguration.DbConnectionString;
//Create a new data provider factory
DbProviderFactory factory = DbProviderFactories.GetFactory(dataProviderName);
//Obtain a database specific connection object
DbConnection conn = factory.CreateConnection();
//Set the connection string
conn.ConnectionString = connectionString;
//Create a database specific command object
DbCommand comm = conn.CreateCommand();
//Set the command type to stored procedure
comm.CommandType = CommandType.StoredProcedure;
//Return the initialised command object
return comm;
}
CatalogAccess.cs
public static class CatalogAccess { static CatalogAccess() { // // TODO: Add constructor logic here // }
//Retrieve the list of departments
public static DataTable GetDepartments()
{
//get configured DbCommand object
开发者_如何学Python DbCommand comm = GenericDataAccess.CreateCommand();
//set the stored procedure name
comm.CommandText = "GetDepartments";
//execute the stored procedure and return the results
return GenericDataAccess.ExecuteSelectCommand(comm);
}
}
DepartementList.ascx.cs
public partial class UserControls_DepartmentsList : System.Web.UI.UserControl { // Load department details into the DataList protected void Page_Load(object sender, EventArgs e) { // don't reload data during postbacks
{
// CatalogAccess.GetDepartments returns a DataTable object containing
// department data, which is read in the ItemTemplate of the DataList
list.DataSource = CatalogAccess.GetDepartments();
// Needed to bind the data bound controls to the data source
list.DataBind();
}
}
}
the ShopConfiguration class
{ //Caches the connection string private readonly static string dbConnectionString;
//Caches the data provider name
private readonly
static string dbProviderName;
//stores the number of products per page
private readonly static int productsPerPage;
//Stores the product description length for product lits
private readonly static int productDescriptionLenght;
//Store the name of your shop
private readonly static string siteName;
//Initialize various proeprties in the constructor
static ShopConfiguration()
{
dbConnectionString = ConfigurationManager.ConnectionStrings["LocalSqlServer"].ConnectionString;
dbProviderName = ConfigurationManager.ConnectionStrings["LocalSqlServer"].ProviderName;
productsPerPage = Int32.Parse(ConfigurationManager.AppSettings["ProductsPerPage"]);
productDescriptionLenght = Int32.Parse(ConfigurationManager.AppSettings["ProductDescriptionLenght"]);
siteName = ConfigurationManager.AppSettings["SiteName"];
}
//Returns the connection string for BeadAfrican database
public static string DbConnectionString
{
get
{
return dbConnectionString;
}
}
//Returns the data provider name
public static string DbProviderName
{
get
{
return dbProviderName;
}
}
I am quite sure that the TypeInitializationException
that is thrown has another exception assigned to its InnerException
property. If you examine that exception, I think you will find the real cause of your problem.
Sounds like you have specified an invalid setting for DbProviderName so internal checking code reports this exception. You'd better review the connection string settings.
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