由网友(给你一口甜甜)分享简介：我想检查我有连接到我的程序的用户名和密码，我已经做了我的查询，但我将如何去有关检查这对一个表的数据库。私人无效的button1_Click（对象发件人，EventArgs的）{菜单M1 =新菜单（）;字符串的connectionString =供应商= Microsoft.ACE.OLEDB.12.0;数据源= Use...

我想检查我有连接到我的程序的用户名和密码，我已经做了我的查询，但我将如何去有关检查这对一个表的数据库。

 私人无效的button1_Click（对象发件人，EventArgs的）
    {
        菜单M1 =新菜单（）;
        字符串的connectionString =供应商= Microsoft.ACE.OLEDB.12.0;数据源= UserAccounts.accdb;坚持安全信息= FALSE;;
        OleDbCommand的CMD =新的OleDbCommand（SELECT * FROM UserAccounts其中用户名=+ userBox.Text +和密码=+ Password.Text +）;
        使用（OleDbConnection的康恩=新的OleDbConnection（的connectionString））
        {
            尝试
            {
                conn.Open（）;
                this.Hide（）;
                m1.Show（）;
            }
            赶上（例外EXC）
            {
                的MessageBox.show（exc.Message）;
            }
        }
    }
 

解决方案

您是pretty的已近，让我们只修改一点点：

 私人无效的button1_Click（对象发件人，EventArgs的）
{
    菜单M1 =新菜单（）;
    字符串的connectionString =供应商= Microsoft.ACE.OLEDB.12.0;数据源= UserAccounts.accdb;坚持安全信息= FALSE;;
    使用（OleDbConnection的康恩=新的OleDbConnection（的connectionString））
    {
        尝试
        {
            conn.Open（）;
            使用（OleDbCommand的CMD =新的OleDbCommand（选择UserAccounts *其中用户名= @用户名和密码= @Password））
            {
                cmd.Parameters.AddWithValue（@用户名，userBox.Text）;
                cmd.Parameters.AddWithValue（@密码，Password.Text）;

                使用（OleDbDataReader R = cmd.ExecuteReader（））
                {
                    如果（r.HasRows）
                    {
                        //做的东西在这里
                    }
                }
            }
            this.Hide（）;
            m1.Show（）;
        }
        赶上（例外EXC）
        {
            的MessageBox.show（exc.Message）;
        }
    }
}
 

I'm trying to check a database that i have connect to my program for user name and password i have my query made but how would i go about checking it against a table.

    private void button1_Click(object sender, EventArgs e)
    {
        Menu m1 = new Menu();
        string connectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=UserAccounts.accdb; Persist Security Info=False;";
        OleDbCommand cmd = new OleDbCommand("Select * from UserAccounts where Username = " +userBox.Text + " and Password] = " + Password.Text + "");
        using (OleDbConnection conn = new OleDbConnection(connectionString))
        {
            try
            {
                conn.Open();
                this.Hide();
                m1.Show();
            }
            catch (Exception exc)
            {
                MessageBox.Show(exc.Message);
            }
        }
    }

解决方案

You're pretty close already, let's just modify it a little bit:

private void button1_Click(object sender, EventArgs e)
{
    Menu m1 = new Menu();
    string connectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=UserAccounts.accdb; Persist Security Info=False;";
    using (OleDbConnection conn = new OleDbConnection(connectionString))
    {
        try
        {
            conn.Open();
            using (OleDbCommand cmd = new OleDbCommand("Select * from UserAccounts where Username = @Username and Password = @Password"))
            {
                cmd.Parameters.AddWithValue("@Username", userBox.Text);
                cmd.Parameters.AddWithValue("@Password", Password.Text);

                using (OleDbDataReader r = cmd.ExecuteReader())
                {
                    if (r.HasRows)
                    {
                        // do something here
                    }
                }
            }
            this.Hide();
            m1.Show();
        }
        catch (Exception exc)
        {
            MessageBox.Show(exc.Message);
        }
    }
}