Check out example codes for "mvc 5 dropdownlist". It will help you in understanding the concepts better.

Code Example 1

//To populate DropDownList using Viewbag, let's create some collection list with 
//selectListItem types and assign to the Viewbag with appropriate name:

public ActionResult Index() {#  
    region ViewBag  
    List < SelectListItem > mySkills = new List < SelectListItem > () {  
        new SelectListItem {  
            Text = "ASP.NET MVC", Value = "1"  
        },  
        new SelectListItem {  
            Text = "ASP.NET WEB API", Value = "2"  
        },  
        new SelectListItem {  
            Text = "ENTITY FRAMEWORK", Value = "3"  
        },  
        new SelectListItem {  
            Text = "DOCUSIGN", Value = "4"  
        },  
        new SelectListItem {  
            Text = "ORCHARD CMS", Value = "5"  
        },  
        new SelectListItem {  
            Text = "JQUERY", Value = "6"  
        },  
        new SelectListItem {  
            Text = "ZENDESK", Value = "7"  
        },  
        new SelectListItem {  
            Text = "LINQ", Value = "8"  
        },  
        new SelectListItem {  
            Text = "C#", Value = "9"  
        },  
        new SelectListItem {  
            Text = "GOOGLE ANALYTICS", Value = "10"  
        },  
    };  
    ViewBag.MySkills = mySkills;#  
    endregion  
    return View();  
}

//And now bind the ViewBag.MySkills values to DropDownlist as below code in view:

<tr>  
    <td> Populating With ViewBag Data </td>  
    <td> @Html.DropDownList("MySkills", (IEnumerable  
        <SelectListItem>)ViewBag.MySkills) </td>  
</tr>

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