在SQL数据库&QUOT错误,必须声明标量变量" [英] Error on sql database "Must declare the scalar variable"
问题描述
我有我的登录系统的问题。我做了一个简单的系统,该系统运行良好,但我想让它更先进,并根据用户的用户类型
显示不同的起始页。不过,我遇到以下错误:必须声明标量变量@UserType
使用系统;
使用System.Data这;
使用System.Data.SqlClient的;
使用System.Configuration;公共部分类LoginwithEncryption:System.Web.UI.Page
{ 保护无效btnSubmit_Click(对象发件人,EventArgs的发送)
{
SqlConnection的CON =新的SqlConnection(ConfigurationManager.ConnectionStrings [构造]的ConnectionString);
con.Open();
CMD的SqlCommand =新的SqlCommand(
SELECT * FROM dbo.UserInfo哪里登录= @登录和用户类型= @用户类型和密码= @密码和用户类型= @的UserType,CON);
cmd.Parameters.AddWithValue(@登录,txtUserName.Text);
cmd.Parameters.AddWithValue(@密码,txtPWD.Text +123);
SqlDataAdapter的大=新SqlDataAdapter的(CMD);
DataTable的DT =新的DataTable();
da.Fill(DT); 如果(dt.Rows.Count大于0)
{
INT用户类型= Convert.ToInt32(dt.Rows [0] [的UserType]);
如果(用户类型== 1)
{
的Response.Redirect(StartPage.aspx);
}
否则如果(用户类型== 2)
{
的Response.Redirect(DiferentStartPage.aspx);
} }
其他
{
ClientScript.RegisterStartupScript(Page.GetType(),验证,
< SCRIPT LANGUAGE =JavaScript的'>警报('无效的用户名和密码)LT; / SCRIPT>中);
} }
}
由于错误状态:必须声明标量变量@UserType
在换句话说,SQL命令有 @UserType
参数,但没有在参数集合中声明的参数。
CMD的SqlCommand =新的SqlCommand(
SELECT * FROM dbo.UserInfo哪里登录= @登录和用户类型= @用户类型和密码= @密码和用户类型= @的UserType,CON);
cmd.Parameters.AddWithValue(@登录,txtUserName.Text);
cmd.Parameters.AddWithValue(@密码,txtPWD.Text +123);
添加另一个参数为 @UserType
参数:
cmd.Parameters.AddWithValue(@用户类型,用户类型);
此外,SQL包含重复引用为 @UserType
:
从dbo.UserInfo选择*
其中,登录= @登录
和用户类型= @用户等级和积分
和密码= @密码
和用户类型= @用户等级和积分
也许应该是:
从dbo.UserInfo选择*
其中,登录= @登录
和密码= @密码
和用户类型= @用户等级和积分
I have a problem with my login system. I made a simple system which worked well, but I wanted to make it more advanced and display a different start page depending on a user's UserType
. However, I'm encountering the following error: "Must declare the scalar variable @UserType."
using System;
using System.Data;
using System.Data.SqlClient;
using System.Configuration;
public partial class LoginwithEncryption : System.Web.UI.Page
{
protected void btnSubmit_Click(object sender, EventArgs e)
{
SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["conStr"].ConnectionString);
con.Open();
SqlCommand cmd = new SqlCommand(
"select * from dbo.UserInfo where Login =@Login and UserType=@UserType and Password=@Password and UserType=@UserType", con);
cmd.Parameters.AddWithValue("@Login", txtUserName.Text);
cmd.Parameters.AddWithValue("@Password", txtPWD.Text+".123");
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataTable dt = new DataTable();
da.Fill(dt);
if (dt.Rows.Count > 0)
{
int usertype = Convert.ToInt32(dt.Rows[0]["UserType"]);
if (usertype == 1)
{
Response.Redirect("StartPage.aspx");
}
else if (usertype == 2)
{
Response.Redirect("DiferentStartPage.aspx");
}
}
else
{
ClientScript.RegisterStartupScript(Page.GetType(), "validation",
"<script language='javascript'>alert('Invalid UserName and Password')</script>");
}
}
}
As the error states: Must declare the scalar variable "@UserType"
In other words, the SQL command has a parameter for @UserType
, but there are no parameters declared in the parameters collection.
SqlCommand cmd = new SqlCommand(
"select * from dbo.UserInfo where Login =@Login and UserType=@UserType and Password=@Password and UserType=@UserType", con);
cmd.Parameters.AddWithValue("@Login", txtUserName.Text);
cmd.Parameters.AddWithValue("@Password", txtPWD.Text+".123");
Add another parameter for the @UserType
parameter:
cmd.Parameters.AddWithValue("@UserType", "User Type");
Also, the SQL contains a duplicate reference to for @UserType
:
select * from dbo.UserInfo
where Login=@Login
and UserType=@UserType
and Password=@Password
and UserType=@UserType
Should probably be:
select * from dbo.UserInfo
where Login=@Login
and Password=@Password
and UserType=@UserType
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