引用不存在的用户控件？

Question

I have created an application that searches a directory and loads all of the usercontrols into the form and then uses a "GetResult()" method to grab the answers from the form. I did not do this OOP style because I am still learning how to fully utilize OOP and I am now going back to design it with OOP so I can move onto the next part which will be a lot easier if I was working with objects. Right now I have created my "RequestForm" class and I want RequestForm.Result to reach into the UC and call the GetResults() method. I am having a difficult time getting it to do this though due to my lack of knowledge perhaps someone can point me in the right direction.

FormUserControl - Abstract Class

namespace AccessRequest
{
    public abstract class FormUserControl : UserControl
    {
        public abstract string Name();
        public abstract string GetResults();
        public abstract string EmailUsers();
    }
}

RequestForm - Object Class

namespace AccessRequest
{
public class RequestForm
{
    public string Name { get; set; }
    public string ControlID { get; set; }
    public string StepName { get; set; }
    public string FilePath { get; set; }
    public string Results { 
        get
        {
            //How would I pull my usercontrol results with Control.GetReults() from within this area?
            //I have since then turned this into a method. How would I get it to access my UserControl loaded on the asp page to grab the results?
        }
        set;
    }
    public string Emails { get; set; }
    public int Position { get; set; }
    public bool Visible { get; set; }

    public RequestForm()
    {

    }
    /// <summary>
    /// FormResults gathers all needed information about the forms
    /// </summary>
    /// <param name="formName">Name of the Form</param>
    /// <param name="formControlID">ID of the User Control </param>
    /// <param name="wizardStepID">ID of the Wizard Step</param>
    /// <param name="formFilePath">File path of the physical form</param>
    /// <param name="formResults">Results from the form</param>
    /// <param name="formEmails">Other emails to include</param>
    public RequestForm(string formName, string formControlId, string wizardStepID, int wizardStepPosition, string formFilePath, string formResults, string formEmails)
    {
        this.Name = formName;
        this.ControlID = formControlId;
        this.StepName = wizardStepID;
        this.Position = wizardStepPosition;
        this.FilePath = formFilePath;
        this.Results = formResults;
        this.Emails = formEmails;
        this.Visible = false;
    }

    public void SaveList(List<RequestForm> formList)
    {
      //  HttpContext.Current.Session["FormList"] = formList;
    }
}

}

Here is the LoadForms() method I put in OnInit to load all of my forms, I have not fully implemented the RequestForm piece but this is where I believe it should go to builder my object list.

private void LoadForms()
    {
        string dotColor = "Black";
        string formColor = "#808080";

        int loc = 3;
        foreach (ListItem item in chklApplications.Items)
        {
            string formPath = (string)item.Value;

            WizardStepBase newStep = new WizardStep();
            newStep.ID = "wzStep" + item.Text;
            newStep.Title = String.Format("<font color='{0}'>  ¤</font> <font color='{1}'>{2} Request</font>", dotColor, formColor, item.Text);


            var form = LoadControl(formPath);
            form.ID = "uc" + item.Text;
            newStep.Controls.Add(form);
            wzAccessRequest.WizardSteps.AddAt(loc, newStep);

            requestForm.Add(new RequestForm(
                                            item.Text,                      //Form name
                                            form.ID.ToString(),             //User Control ID
                                            newStep.ID.ToString(),          //Wizardstep ID
                                            loc,                            //Wizardstep Position
                                            item.Value.ToString(),          //File Path    
                                            null,                           //Form Results
                                            null                            //Form Emails
                                            ));
            loc++;
        }

    }

Here is where I set whether they are visible or not in my side menu of the Wizard Control. BTW, does anyone know how I can prevent it from even creating the table tags for this? Right now it is growing a large space where I am inserting the forms.

protected void SideBarList_ItemDataBound(object sender, DataListItemEventArgs e)
    {
        if (e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem)
        {
            if (!ShowWizardStep(e.Item.DataItem))
            {
                e.Item.CssClass = "Hidden";

            }

        }
    }

Thanks for any advise I receive!! :D

Answer 1

Ok, so I figured this out. I already had a method that would gather all the results from the form and then spit them out on the verification screen. I manipulated that code so that now it loads them directly into the object I was working with. Now my objects are full of all the dynamic information I need for my controls and I can manage them a lot easier. Here is the code in case anyone else is looking for the answer.

MyClass

public class RequestForm
{
    public string Name { get; set; }
    public string ControlID { get; set; }
    public string StepID { get; set; }
    public string FilePath { get; set; }
    public string Emails { get; set; }
    public string Results { get; set; }
    public int Position { get; set; }
    public bool Visible { get; set; }

    /// <summary>
    /// FormResults gathers all needed information about the forms
    /// </summary>
    /// <param name="formName">Name of the Form</param>
    /// <param name="formControlID">ID of the User Control </param>
    /// <param name="wizardStepID">ID of the Wizard Step</param>
    /// <param name="formFilePath">File path of the physical form</param>
    /// <param name="formResults">Results from the form</param>
    /// <param name="formEmails">Other emails to include</param>
    public RequestForm(string formName, string formControlId, string wizardStepID, int wizardStepPosition, string formFilePath, string formEmails,string formResults, bool formVisible = false)
    {
        this.Name = formName;
        this.ControlID = formControlId;
        this.StepID = wizardStepID;
        this.Position = wizardStepPosition;
        this.FilePath = formFilePath;
        this.Emails = formEmails;
        this.Results = formResults;
        this.Visible = formVisible;
    }
}

This list that holds all of the controls

    public List<RequestForm> requestForm
    {
        get
        {
            List<RequestForm> requestList = new List<RequestForm>();
            requestList = (List<RequestForm>)Session["RequestForms"];
            var v = Session["RequestForms"];
            return v != null ? (List<RequestForm>)v : null;
        }
        set
        {
            Session["RequestForms"] = value;
        }
    }

This is the method that I use to gather the results and then put them into the object.

    private void GatherFormsData()
    {
        if (requestForm != null)
        {
            foreach (RequestForm rform in requestForm)
            {
                if (rform.Visible)
                {
                    WizardStepBase step = (WizardStep)wzAccessRequest.FindControl(rform.StepID);
                    FormUserControl form = (FormUserControl)step.FindControl(rform.ControlID);
                    rform.Results = String.Format("{0}<br>Email: {1}<br><br>", form.GetResults(), form.EmailContact());
                }
            }
        }
    }

Hope this helps someone.

Answer 2

There are several problems you need to address — both in your code and both in your current knowledge :-) Start with this:

1. Read a few articles about ASP.NET's page life-cycle, so you become more familiar with what to do in each life-cycle event handler ( OnInit , OnLoad , …). Good starting point might be this MSDN overview . However, google for “ASP.NET page life cycle” and read a few other articles and examples as well.

   Also, you will need to get familiar with the request-response nature of ASP.NET page processing. In the beginning, bear in mind that when the user hits some 'Submit' button which in turn causes an HTTP POST request to occur, you are responsible to creating the page's control tree to match its structure, IDs, etc. as they were in the previous request. Otherwise ASP.NET doesn't know how in which controls to bind the data the user filled-in.

2. Near the line tagged //Lost and confused here :/ you are creating a new control and immediately querying it for the 'results' (which I expect to be values of some edit boxes within it). This cannot work, because it's most probably too early for the form to have the data received from the Page object that drives the request processing.

3. Your Results property is poorly designed. First, you shouldn't be using properties that actually 'generate' data in such a way they can change without notice. Properties shall be used as “smart fields”, otherwise you end up with less manageable and less readable code. Second, the setter you left there like “set;” causes any value assigned into the property to be actually lost, because there's no way to retrieve it. While in some rare cases this behavior may be intentional, in your case I guess it's just an error.

So, while you can currently leave behind any “good OOP way” to approach your problem, you certainly should get more familiar with the page life-cycle. Understanding it really requires some thinking about the principles how ASP.NET web applications are supposed to work, but I'm sure it will provide you with the kick forward you actually need.

UPDATE: In respect to Tony's code (see comments) the following shall be done to move the code forward:

1. The list of form data in the requestForm property shall have tuple of [form ASCX path, control ID, the actual RequestForm data class]

2. GatherForms shall be called only when the page is initially loaded (ie if (Page.IsPostBack) ) and it shall fill requestForm with the respective tuples for available ASCX forms.

3. Both chklApplications and wizard steps shall be created in LoadForms on the basis of requestForm 's content.

4. When results are to be gathered, the ID stored in the respective requestForm entry can be used to look-up the actual user control.