hi
I use 2 Textboxs for searching Items in database :
HTML-
<div class="form inline">
    @using (Ajax.BeginForm("Search", "Test", new AjaxOptions { HttpMethod = "Post",
    InsertionMode = InsertionMode.Replace, LoadingElementId = "imgLoading", LoadingElementDuration
    = 1000, Url = "/Test/Search", UpdateTargetId = "divSearch" })) {
    <div class="group">
        @Html.Label("جستجو روی نام", new { @class = "label" })
        <div class="controls">
            @Html.TextBox("txtSearchName", null, new { @class = "text", style = "width: 240px;"
            })
        </div>
    </div>
    <div class="group">
        @Html.Label("جستجو روی آدرس", new { @class = "label" })
        <div class="controls">
            @Html.TextBox("txtSearchAddress", null, new { @class = "text", style = "width: 240px;"
            })
        </div>
    </div>
</div>
and:
Code -
public ActionResult Search(string txtSearchName, string txtSearchAddress)
{
    System.Threading.Thread.Sleep(2000);
    var blReseller = new ResellerRepository();
    var model = blReseller.Where(p => p.Name.Contains(txtSearchName) && p.Address.Contains(txtSearchAddress)).ToList();
    return PartialView("_SearchReseller", model);
}
as you see in above action I use txtSearchName and txtSearchAddress (2 textbox's Id) for searching data in database
now I want define DropdownList that users can select Item from Dropdownlist and click button to search in database below is code:
 
<div>
    <div class="form inline">
        @using (Ajax.BeginForm("Search", "Test", new AjaxOptions { HttpMethod = "Post",
        InsertionMode = InsertionMode.Replace, LoadingElementId = "imgLoading", LoadingElementDuration
        = 1000, Url = "/Test/Search", UpdateTargetId = "divSearch" })) {
        <div class="group">
            @Html.Label("جستجو روی نام", new { @class = "label" })
            <div class="controls">
                @Html.DropDownListFor(model => model.Ostans, Model.Ostans1, "Please select")
            </div>
        </div>
        <div class="group">
            @Html.Label("جستجو روی آدرس", new { @class = "label" })
            <div class="controls">
                @Html.DropDownListFor(model => model.Citeies1, Model.Citeies1, "Please select")
            </div>
        </div>
        <div class="block-standart">
            <div class="form">
                <div class="group">
                    <div class="controls">
                        <img src="~/Content/Images/loading (1).gif" id="imgLoading" style="display: none" />
                        <button class="button">
                            جستجو</button>
                    </div>
                </div>
            </div>
        </div>
    </div>
</div>
} @Html.Partial("_SearchReseller", Model)
now I want in ACTION use DropDownList Selected Item and search in database how I can use it in below action
public ActionResult Search(string txtSearchName, string txtSearchAddress)
{
    System.Threading.Thread.Sleep(2000);
    var blReseller = new ResellerRepository();
    var model = blReseller.Where(p => p.Name.Contains(txtSearchName) && p.Address.Contains(txtSearchAddress)).ToList();
    return PartialView("_SearchReseller", model);
}
best regards
Neda