这是我的代码
SqlCommand cmd = new SqlCommand("spRegisterUser", con);
cmd.CommandType = CommandType.StoredProcedure;
SqlParameter username = new SqlParameter("@UserName", txtUserName.Text);
SqlParameter password = new SqlParameter("@Password", txtPassword);
SqlParameter email = new SqlParameter("@Email", txtEmail.Text);
SqlParameter userType = new SqlParameter("@UserType", SqlDbType.NVarChar, 200);
userType.Value = "Student";
cmd.Parameters.Add(username);
cmd.Parameters.Add(password);
cmd.Parameters.Add(email);
cmd.Parameters.Add(userType);
con.Open();
int ReturnCode = (int)cmd.ExecuteScalar(); //This is where it displays error message
if (ReturnCode == -1)
有什么想法吗?
这是错误消息
不存在从对象类型 System.Web.UI.WebControls.TextBox 到已知托管提供程序本机类型的映射。
说明:执行当前 Web 请求期间发生未经处理的异常。请查看堆栈跟踪,了解有关错误及其在代码中起源位置的详细信息。
异常详细信息:System.ArgumentException:不存在从对象类型 System.Web.UI.WebControls.TextBox 到已知托管提供程序本机类型的映射。
源错误:
Line 48: con.Open(); Line 49: Line 50: int ReturnCode = (int)cmd.ExecuteScalar(); Line 51: if (ReturnCode == -1) Line 52: {
源文件:c:\Users\Mubashir\Documents\Visual Studio 2012\Projects\Sit302GroupProject\Sit302GroupProject\Registration\Registration.aspx.cs 行:50
堆栈跟踪:
[ArgumentException: No mapping exists from object type System.Web.UI.WebControls.TextBox to a known managed provider native type.] System.Data.SqlClient.MetaType.GetMetaTypeFromValue(Type dataType, Object value, Boolean inferLen, Boolean streamAllowed) +2021139 System.Data.SqlClient.SqlParameter.GetMetaTypeOnly() +5287377 System.Data.SqlClient.SqlParameter.Validate(Int32 index, Boolean isCommandProc) +16 System.Data.SqlClient.SqlCommand.SetUpRPCParameters(_SqlRPC rpc, Int32 startCount, Boolean inSchema, SqlParameterCollection parameters) +122 System.Data.SqlClient.SqlCommand.BuildRPC(Boolean inSchema, SqlParameterCollection parameters, _SqlRPC& rpc) +78 System.Data.SqlClient.SqlCommand.RunExecuteReaderTds(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, Boolean async, Int32 timeout, Task& task, Boolean asyncWrite) +1379 System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method, TaskCompletionSource`1 completion, Int32 timeout, Task& task, Boolean asyncWrite) +175 System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method) +53 System.Data.SqlClient.SqlCommand.ExecuteScalar() +149 Sit302GroupProject.Registration.btnRegister_Click(Object sender, EventArgs e) in c:UsersMubashirDocumentsVisual Studio 2012ProjectsSit302GroupProjectSit302GroupProjectRegistrationRegistration.aspx.cs:50 System.Web.UI.WebControls.Button.OnClick(EventArgs e) +9552602 System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) +103 System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +10 System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +13 System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +35 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1724
这是存储过程
CREATE proc spRegisterUser
@Username nvarchar(100),
@Password nvarchar(200),
@Email nvarchar(200),
@UserType nvarchar(200),
as
Begin
Declare @Count int
Declare @ReturnCode int
Select @Count = COUNT(UserName)
from tblUsers where UserName = @UserName
If @COunt > 0
Begin
Set @Return = -1
End
Else
Begin
Set @ReturnCode = 1
Insert into tblUsers values
(@UserName, @Password, @Email, @UserType)
End
Select @ReturnCode as ReturnValue
End
您正在传递txtPassword
这是文本框的对象,因此您得到异常。
问题出在内
SqlParameter password = new SqlParameter("@Password", txtPassword);
因此,请将您的代码更改为
SqlParameter password = new SqlParameter("@Password", txtPassword.Text);
这是一个用于将 SQL 参数传递给存储过程的函数:
public static SqlParameter Parameter( SqlDbType dbtype, string ParameterName, string Value)
{
SqlParameter param = new SqlParameter();
param.ParameterName = ParameterName;
param.SqlDbType = dbtype;
param.SqlValue = Value;
return param;
// cmd.Parameters.Add(param);
}
你可以像这样使用它的函数
SqlCommand cmd = new SqlCommand("SP_Name");
cmd.Parameter.Add(Parameter(SqlDbType.DateTime,"@Parameter",DateTimepicker.Text));
或
SqlParameter[] parameters =
{
new SqlParameter("@Task", "insert"),
new SqlParameter("@Name", clsPluginHelper.DbNullIfNullOrEmpty(txtinstalName.Text)),
new SqlParameter("@Descp", clsPluginHelper.DbNullIfNullOrEmpty(txtInstDescp.Text)),
clsPluginHelper.Parameter(SqlDbType.DateTime, "@StartDate",dtpInstStartDate.Text),
clsPluginHelper.Parameter(SqlDbType.DateTime, "@EndDate",dtpInstalEndDate.Text)
};