CODEWITHSUNDEEP
c#.netwinforms
user2783193
user2783193

Reputation: 1022

one winform to add and update data

I usually in my web projects use one webform for adding and update data. I just scratched winforms environment so I was thinking to use same approach one form to add and update data.

I was thinking to use two constructors on addEditForm like

public AddEditForm()
{
   .. to do new object
}
public AddEditForm(MyDataObj obj)
{      
   ... to do edit
}

so, is this right approach or is there better practice?

thanks

Upvotes: 1

Views: 68

Answers (4)

G.Y
G.Y

Reputation: 6159

The correct approach would be:

public partial class CustomerForm: Form
{
    private object instance;

    public CustomerForm()
    {
        InitializeComponent();
        SetData(BLL.CreateNewEmptyObject());
    }

    public CustomerForm(object details)
        : this()
    {
        SetData(details);
    }

    public void SetData(object details)
    {
        instance = details;
        //bind the details to controls 
    }

    private void Save()
    {
        BLL.Save(instance);
    }

   public bool EnableEdit {get{... 
}

Usage Examples:

    var newCustomerFrm = new CustomerForm();

    var existingCustomerFrmReadOnly = new CustomerForm(BLL.GetCustomerById("123"))
    {
        EnableEdit = false
    };

    var existingCustomerFrmToEdit = new CustomerForm(BLL.GetCustomerById("123"))
    {
        EnableEdit = true
    };

Upvotes: 0

VahidNaderi
VahidNaderi

Reputation: 2488

As I said in my comment I use this approach too, of course when I'm not using MVP(which is a different story)

About calling InitializeComponent() you need it in your form construction because it is the method which (as you can tell from it's name) initializes your form and controls on it and without it you'll get an empty form.

But if you are concerned about calling InitializeComponent() twice, I prefer this:

MyDataObj _myObject;
public AddEditForm()
{
    InitializeComponent();
}

public AddEditForm(MyDataObj obj)
    :this()
{      
    if(obj == null) //you're creating the object
       _myObject = new MyDataObj();
    else // you're editing it
        _myObject = obj;
}
// Continue my work with _myObject

Upvotes: 2

Virus
Virus

Reputation: 2541

You can create different constructors in the following way:

MyDataObj editItem=null;
public AddEditForm()
{      
   InitializeComponent();
   //Other common code for initialization.
}

public AddEditForm(MyDataObj obj) : this()
{      
    editItem = obj;
    //Other code specific to editing.
}

If the object editItem is null, then the form can be considered in Add mode, otherwise Edit mode.

A property also can be made for the same For example:

public bool IsEditMode
{
    get
    {
        return (editItem != null);
    }
}

hope it helps...

Upvotes: 2

Florian
Florian

Reputation: 1887

The approach you posted is the normal approach for creating such a form.

But sometimes you will see something like this. 

public AddEditForm(MyDataObj obj, int mode) //1 = edit, 2 = create
{      
   ... to do edit
}

If you think about it, this is not a good alternative. It's harder to understand and looks ugly.

Do I need to call InitializeComponent() in every constructor?

Unless you do constructor chaining (which would not work here), yes you do. Please look @Virus answer for a way to only call it once.

Upvotes: 0

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