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

本文关键字：类型 本机 映射 程序 System 对象 Web UI 不存在 TextBox WebControls | 更新日期: 2023-09-27 18:34:12

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:'Users'Mubashir'Documents'Visual Studio 2012'Projects'Sit302GroupProject'Sit302GroupProject'Registration'Registration.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

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

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)
};
相关文章：