pass value of drop down list from view to controller

Question

i have this dropdpwn list  i want to pass the slected value from it to contoller 

@Html.DropDownListFor(model => model.Contant.KEYWORD_NAME, ViewData["KEYWORD_NAME"] as IEnumerable<SelectListItem>, "Select Company Name", new { @class = "form-control" })

i use this way to pass value from view to contoller 

@if (Model != null)

{

@Html.PagedListPager(Model.Items,page => Url.Action("search", new { page, search = Request.QueryString["search"] , KEYWORD = ViewData["KEYWORD_NAME"].ToString()}),

new PagedListRenderOptions()

{

Display = PagedListDisplayMode.IfNeeded,

DisplayPageCountAndCurrentLocation = true

,

DisplayItemSliceAndTotal = true

})

}

 

but in the contoller 

public ActionResult search(int? page, string search, String KEYWORD)

 the value of  KEYWORD set to be "NULL " 
in the  URL broswer the KEYWORD vlue not null