4 c#-2.0
我正在忙着使用visual studio 2005和IIS 7的电子商务Web应用程序
我收到了这个错误
用户代码未处理System.TypeInitializationException
Message ="'ShopConfiguration'的类型初始值设定项引发异常."
源= "App_Code.r-ihwy-d"
类型名= "ShopConfiguration"
堆栈跟踪:
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)
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如果我查看它所指的代码,我不会看到有什么问题?这是代码,如果有人可以请帮助它会很棒!
GenericDataAccess.cs:
public static class GenericDataAccess {// static constructor static GenericDataAccess(){// // TODO:在这里添加构造函数逻辑//}
//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;
}
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CatalogAccess.cs
public static class CatalogAccess {static CatalogAccess(){// // TODO:在这里添加构造函数逻辑//}
//Retrieve the list of departments
public static DataTable GetDepartments()
{
//get configured DbCommand object
DbCommand comm = GenericDataAccess.CreateCommand();
//set the stored procedure name
comm.CommandText = "GetDepartments";
//execute the stored procedure and return the results
return GenericDataAccess.ExecuteSelectCommand(comm);
}
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}
DepartementList.ascx.cs
公共部分类UserControls_DepartmentsList:System.Web.UI.UserControl {//加载部门详细到DataList的保护无效的Page_Load(对象发件人,EventArgs的){//不重装回发过程中的数据
{
// 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();
}
}
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}
ShopConfiguration类
{//缓存连接字符串private readonly静态字符串dbConnectionString;
//Caches the data provider name
private readonly
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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;
}
}
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