MVC / HTML.DropDownListFor / making default option and its value

Question

I have CreateForm action in ProductController. This action uses view with model: ProductSupplierViewModel (consists of Product and List<Supplier> Suppliers).

In my CSHTML i have

@Html.LabelFor(m => m.Product.Supplier)
@Html.DropDownListFor(m => m.Product.Supplier.Id, new SelectList(Model.Suppliers, "Id", "Name"), "", new { @class = "form-control" })

BUT, this way i only have my default option set to blank (by using two quotation makrs in html helper).

What i need to know is:

how to set a value="0" to that blank option?
Does the web have default value if we dont specify one for it or?

Trying to get 0 because in my DataAccessLayer i have CreateProduct(Product p) method where i'll specify:

if(p.Supplier.Id == 0) // from parameter
{ 
  *put NULL value in this DB field*
}

derloopkat · Accepted Answer · 2020-10-28T01:12:48.587

The most simple is:

@Html.DropDownListFor(m => m.Product.Supplier.Id, 
    new SelectList(Model.Suppliers, "Id", "Name", 0),
    "Please Select...",
    new { @class = "form-control" })

This creates a default item "Please Select...". However it's mandatory to select an item different than the default.

If selecting an item is not mandatory, you can do:

Controller

model.Suppliers.Insert(0, new Supplier()
{
    Id = 0,
    Name = "Please Select..."
});

View

@Html.DropDownListFor(m => m.Product.Supplier.Id, 
    new SelectList(Model.Suppliers, "Id", "Name", 0), 
    new { @class = "form-control" })

MVC / HTML.DropDownListFor / making default option and its value

1 Answers1