这样写登录方法对吗？

[飞扬残月]

public bool DengLu(string name, string pwd)
{
StringBuilder strSQl = new StringBuilder();
OleDbParameter[] newsParms=new OleDbParameter[]{
new OleDbParameter("@name",OleDbType.Char,20),
new OleDbParameter("@pwd",OleDbType.Char,20)};
OleDbCommand cmd=new OleDbCommand();
newsParms[0].Value=name;
newsParms[1].Value=pwd;
foreach (OleDbParameter parm in newsParms)
cmd.Parameters.Add(parm);
using (OleDbConnection conn=new OleDbConnection(CONN_STRING))
{
strSQl.Append("SELECT * FROM semply where sname=@name and spass=@pwd");
conn.Open();
cmd.Connection=conn;
cmd.CommandType=CommandType.Text;
cmd.CommandText=strSQl.ToString();
int val = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
if (val > 0)
return true;
else
return false;

}
}

[migercai]

有错吗？

[zhong2006]

可以！！

[飞扬残月]

这是我登录按钮的代码，但是label3，不显示
using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{

}
protected void Button1_Click(object sender, EventArgs e)
{
userlogin mylogin = new userlogin();
if (mylogin.DengLu(Txtuser.Text, txtpwd.Text))
{
Session["username"] = Txtuser.Text;
Session["userpass"] = txtpwd.Text;
Label3.Text = "登录成功";
}
else
{
Label3.Text = "登录失败";
}

}
}

[fox1025701]

没问题

[migercai]

label3，不显示
是不是不原来隐藏了
你可以直接弹出提示的

  Response.write("<javascript>alert('登陆成功！');</javascript>");

[Teng_s2000]

     using (OleDbConnection conn=new OleDbConnection(CONN_STRING)) 
        { 
            strSQl.Append("SELECT count(*) FROM semply where sname=@name and spass=@pwd"); 
            conn.Open(); 
            cmd.Connection=conn; 
            cmd.CommandType=CommandType.Text; 
            cmd.CommandText=strSQl.ToString(); 
            int val =Convert.ToInt32( cmd.ExecuteScalar().ToString()); //select 语句用
            //cmd.Parameters.Clear(); 
            if (val ==1) 
                return true; 
            else 
                return false; 

        } 

[Teng_s2000]

ls的同志们太不负责任了吧,ExecuteNonQuery都不返回值了,还对???

[飞扬残月]

总是显示登陆错误，即使用户名和密码正确

[migercai]

[Quote=引用 7 楼 Teng_s2000 的回复:]
ls的同志们太不负责任了吧,ExecuteNonQuery都不返回值了,还对???
[/Quote]
没注意
确实不返回值

[larry_seven]

ExecuteNonQuery这个只对insert delete update 有用你写的是select要用ExecuteReader才行

[飞扬残月]

int val =Convert.ToInt32(cmd.ExecuteReader().ToString());
这么写也不对呢？

[Riverwcj]

没问题的...

[yijianxiangde100]

    cmd.CommandText = "SELECT COUNT(*) FROM Member WHERE name=@vname AND password=@vpassword";
            cmd.Parameters.Add("@vname", SqlDbType.Char);
            cmd.Parameters["@vname"].Value = name;
            cmd.Parameters.Add("@vpassword", SqlDbType.Char);
            cmd.Parameters["@vpassword"].Value = password;
            conn.Open();
                int count = 0;
                count = (int)cmd.ExecuteScalar();

lz 用我的这个方法试一试？看行不行？

[yuyantianya]

public bool DengLu(string name, string pwd)
{
StringBuilder strSQl = new StringBuilder();
OleDbParameter[] newsParms=new OleDbParameter[]{
new OleDbParameter("@name",OleDbType.Char,20),
new OleDbParameter("@pwd",OleDbType.Char,20)};
OleDbCommand cmd=new OleDbCommand();
newsParms[0].Value=name;
newsParms[1].Value=pwd;
foreach (OleDbParameter parm in newsParms)
cmd.Parameters.Add(parm);
using (OleDbConnection conn=new OleDbConnection(CONN_STRING))
{
strSQl.Append("SELECT Count(*) FROM semply where sname=@name and spass=@pwd");
conn.Open();
cmd.Connection=conn;
cmd.CommandType=CommandType.Text;
cmd.CommandText=strSQl.ToString();
int val = cmd.ExecuteScalar();
cmd.Parameters.Clear();
if (val > 0)
return true;
else
return false;

}
}
上面是正解，你可以试试

[zouzedong]

楼上的对的·

[gg_lihui]

路过

[鱼C缸]

可以，

[别样苍茫]

解决了

[飞扬残月]

错误 1 无法将类型“object”隐式转换为“int”。存在一个显式转换(是否缺少强制转换?) E:\oa\App_Code\userlogin.cs 45 23 E:\oa\