C#

allan.gagnon wrote:

I want to make a Login class that I pass info from a text box in to a set variable in the class and then use a get variable to test if my login was successfull. Is this possible?

class MyClass
{
    private string someField; // AKA: member variable
 
    public string SomeProperty
    {
        get
        {
            return this.someField;
        }
        set
        {
            this.someField = value;
        }
    }
}

class Login
{
    private bool isLoggedIn;
 
    public void AuthenticateUser(string userName, string password)
    {
        // Do what you need to do to authenticate the user
    }
 
    public bool IsLoggedIn
    {
        // A getter only because we don't want the outside world to
        // be able to set IsLoggedIn.
        get
        {
            return this.isLoggedIn;
        }
    }
}

allan.gagnon wrote:

However I am getting this error message when I build my project:

Error 1 Property or indexer 'System.Data.Common.DbDataReader.this[string]' cannot be assigned to -- it is read only C:\Documents and Settings\admin\My Documents\Visual Studio 2005\Projects\GasCabinetSimulator\GasCabinetSimulator\ClassLogin.cs 46 37 GasCabinetSimulator

This line is the error: rdr["IsLoggedIn"] = true;

UPDATE tblLogin SET IsLoggedIn = 1 WHERE UserID = ????

SELECT COUNT(*) FROM tblLogin WHERE UserID = @userID AND Password = @password

SqlCommand cmd = new SqlCommand();
cmd.CommandText = "SELECT COUNT(*) FROM tblLogin "+
                  "WHERE UserID = @userID AND Password = @password";
cmd.Connection = cn;
cmd.Parameters.Add("@userId", theUserId);
cmd.Parameters.Add("@password", thePassword);
int matches = (int)cmd.ExecuteScalar();
if (matches == 0)
{
    // No match - user is not logged in
}
else
{
   // A match has been found - user can be logged in.
}

<br />
public class Blah:IDisposable<br />
{<br />
    public void Dispose()<br />
    {<br />
        //Dispose Here<br />
    }<br />
}<br />

<br />
myBlahObject.Dispose();<br />

<br />
public class Blah:IDisposable<br />
{<br />
    void IDisposable.Dispose()<br />
    {<br />
        //Dispose Here<br />
    }<br />
}<br />

<br />
myBlahObject.Dispose();<br />

<br />
(myBlahObject as IDisposable).Dispose();<br />

<br />
public abstract class myAbstractClass:IDisposable<br />
{<br />
    public abstract void Blah();<br />
    //some methods here<br />
    void IDisposable.Dispose()<br />
    {<br />
    }<br />
}<br />

<br />
public class myImplementedClass:myAbstractClass<br />
{<br />
    private ClassThatNeedsToBeCleanedUpOnDispose foo;<br />
    public override void Blah()<br />
    {<br />
         // do some blah's here<br />
    }<br />
    public override void Dispose() //this will give you a Compiler Error<br />
    {<br />
         // clean up you foo here<br />
    }<br />
}<br />

<br />
public abstract class MyAbstractClass:IDisposable<br />
{<br />
    public abstract void Blah();<br />
    void IDisposable.Dispose()<br />
    {<br />
        Dispose(true);<br />
    }<br />
    protected virtual void Dispose(bool Disposing)<br />
    {<br />
        // clean up here..<br />
    }<br />
}<br />

<br />
public class myImplementedClass:myAbstractClass<br />
{<br />
    private ClassThatNeedsToBeCleanedUpOnDispose foo;<br />
    public override void Blah()<br />
    {<br />
         // do some blah's here<br />
    }<br />
    protected override void Dispose(bool Disposing)<br />
    {<br />
        if (Disposing)<br />
        {<br />
            // clean up you foo here<br />
            base.Dispose(Disposing);<br />
        }<br />
    }<br />
}<br />
<br />

<br />
myAbstractClass blah = new derivedfromthederivedClassFrommyAbstractClass();<br />
(blah as IDisposable).Dispose();<br />