c# - how to filter between dates in ASP.NET Web Application -

i new mvc , software development, , want implement search date functionality within application. on index view want users able search 2 date fields available on web page, "date" , "order date". code have in view, specifies layout of page.

using (html.beginform("index","purchaseorder",formmethod.get)) {     <p>         search date: &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;@html.textbox("searchby","datesearchbegin") to: @html.textbox("searchby","datesearchend")         <input type="submit" value="search" /> <br /><br />         search order date: &nbsp;@html.textbox("searchby","dateorderedbegin") to: @html.textbox("searchby","dateorderedend")         <input type="submit"  value="search" />         <br /> <br />         search by: @html.radiobutton("searchby","requestor", true) requestor         @html.radiobutton("searchby","vendor") vendor         @html.radiobutton("searchby","workorder") work order # <br />         @html.textbox("search","", new { style = "width:10000px" })         <input type="submit" value="search"  />     </p>  } 

in controller, have code. trying provide logic able filter different fields.

// get: purchaseorder public actionresult index(string searchby, string search,  int? page) {      if (searchby == "requestor")     {         return view(db.purchaseorders.where(x => x.requestor.toupper().contains(search)).orderby(i => i.dateordered).topagedlist(page ?? 1, 15));     }     else if (searchby == "vendor")     {         return view(db.purchaseorders.where(x => x.vendor.toupper().contains(search)).orderby(i=>i.dateordered).topagedlist(page??1,15));     }     else if (searchby == "workorder")     {         return view(db.purchaseorders.where(x => x.purchaserequest_.toupper().contains(search)).orderby(i => i.dateordered).topagedlist(page ?? 1, 15));     }     else if (searchby == "datesearchbegin")     {         return view(db.purchaseorders.where(x => x.date > "datesearchbegin" && x.date < "datesearchend").orderby(i => i.date).topagedlist(page ?? 1,15));     }     else if (searchby == "datesearchend")     {         return view(db.purchaseorders.where(x => x.date > "dateorderedbegin" && x.date < "dateorderedend").orderby(i => i.date).topagedlist(page ?? 1,15));     }     int pagesize = 15;     int pagenumber = (page ?? 1);     pagenumber = page == null ? (viewbag.pagedata == null ? 1 : (int)viewbag.pagedata) : page.value;     viewbag.pagedata = page;     return view(db.purchaseorders.orderby(i => i.dateordered).topagedlist(pagenumber, pagesize)); } 

i getting error message states "operator '<' cannot applied operands of type 'system.datetime?' , 'string'. how can fix error, , there more efficient way code achieve trying do?

you need construct datetime object query (string search) , use in linq query.

var dtfrom = datetime.parse(search) var dtto ...  return view(db.purchaseorders.where(x => x.date > dtfrom && x.date < dtto).orderby(i => i.date).topagedlist(page ?? 1,15)); 

but need introduce ability search multiple properties @ once. can achieve returning iqueryable linq queries , subsequent queries on it. way can concatenate multiple queries:

var filtered = db.purchaseorders.where(x => ...).asqueryable();  filtered = filtered.where(x => ...).asqueryable(); 

etc

and return

filtered.topagedlist()