Private Sub BtnLogin_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnLogin.Click
Dim conn As New System.Data.SqlClient.SqlConnection
Dim cmd As New System.Data.SqlClient.SqlCommand
Dim objReader As System.Data.SqlClient.SqlDataReader
conn.ConnectionString = "server=localhost;uid=sa;pwd=123;database=myweb"
conn.Open()
cmd.Connection = conn
cmd.CommandText = "select userID from member"
objReader = cmd.ExecuteReader()
Dim i As Integer
While objReader.Read()
If objReader.GetValue(i) = TxtID.Text Then
Response.Redirect("AlreadyExists.aspx?ID=" & TxtID.Text)
conn.Close()
End If
End While
conn.Close()
End Sub
好像IF判断根本不起作用,怎么回事呢?
Dim conn As New System.Data.SqlClient.SqlConnection
Dim cmd As New System.Data.SqlClient.SqlCommand
Dim objReader As System.Data.SqlClient.SqlDataReader
conn.ConnectionString = "server=localhost;uid=sa;pwd=123;database=myweb"
conn.Open()
cmd.Connection = conn
cmd.CommandText = "select userID from member"
objReader = cmd.ExecuteReader()
Dim i As Integer
While objReader.Read()
If objReader.GetValue(i) = TxtID.Text Then
Response.Redirect("AlreadyExists.aspx?ID=" & TxtID.Text)
conn.Close()
End If
End While
conn.Close()
End Sub
好像IF判断根本不起作用,怎么回事呢?
cmd.CommandText = "select userID from member where userid ='"+TxtID.Text.Trim()+"'"
objReader = cmd.ExecuteReader()
Dim i As Integer
if(objReader.Read())
{
Response.Redirect("AlreadyExists.aspx?ID=" & TxtID.Text)} conn.Close()
Dim conn As New System.Data.SqlClient.SqlConnection
在页面前加上:imports System.Data.SqlClient
后面就可以这样写了 :Dim conn As New SqlConnection
sql中建一个过程:
IsHaveUserName
@Username varchar(50),
@Result int output
as
select * from Tuser where UserName=@userName
if(@@rowcount>0)
begin
set @Result=1
end
else
begin
set @Result=0
end然后用程序来判断
SqlCommand com=new SqlCommand("IsHaveUserName",conn)
com.commandType=commandType.storexxxx;
sqlparameter UserName=new sqlparameter("@userNmae",sqlDbtype.varchar)
username=txtusername.text;
com.parameters.add(username);sqlparameter Result=new sqlparameter("@Result",sqlDbtype.int)
Result.direction=output;
com.parameters.add(Result);conn.open();
com.executenoquery();
conn.close();if(Result.value==1)
{
you same!!
}
esle
{
no same!!
}
时间急,有点乱……。