While binding dropdown in MVC, I always get this error: There is no ViewData item of type \'IEnumerable.
your code is correct because in some cases it does not work, I also do not know where the error comes from but this can help you solve the problem, move the code in the head of the view like this:
index.cshtml:
@using expert.Models;
@{
ViewBag.Title = "Create";
Layout = "~/Views/Shared/_Layout.cshtml";
Manager db = new Manager();
ViewBag.FORM_PRESTATION = new SelectList(db.T_BDE_PRESTATION_PRES.OrderBy(p => p.PRES_INTITULE).Where(p => p.T_B_PRES_ID == null), "PRES_ID", "PRES_INTITULE");
}
@Html.DropDownList("FORM_PRESTATION", null, htmlAttributes: new { @class = "w3-select ", @required = "true" })