Member Avatar for haymen.roth.3

In if else structure when null arguments are passed to two string variables then it always hit the condition when i have set Var1 != "" && Var2 != "" why ? since nulls are passed to both then why it hits this condition ?

code:

 public ActionResult ShowCalTextBox(String DateFrom, String DateTo) 
        {

           if (DateFrom != "" && DateTo == "") 
            {
                IEnumerable<GetEmpRec_DateResult> EmpRec_DateFrom = DataContext.GetEmpRec_Date(DateFrom, null).ToList();
                ViewBag.Dates = "Records for"+" "+ DateFrom ;
                return View(EmpRec_DateFrom);

            }
            else if (DateFrom == "" && DateTo != "") 
            {
                IEnumerable<GetEmpRec_DateResult> EmpRec_DateTo = DataContext.GetEmpRec_Date(null, DateTo).ToList();
                ViewBag.Dates = "Records for" + " " + DateTo;
                return View(EmpRec_DateTo);
            }
            else if (DateFrom != "" && DateTo != "") 
            {
                IEnumerable<GetEmpRec_DateResult> EmpRec_ByDate = DataContext.GetEmpRec_Date(DateFrom, DateTo).ToList();
                ViewBag.Dates = "Records from" + " " + DateFrom +" "+"to"+" "+DateTo;
                return View(EmpRec_ByDate);
            }
            else if (DateFrom == "" && DateTo == "")
            {
                IEnumerable<GetEmpRec_DateResult> EmpRec_Default = DataContext.GetEmpRec_Date(null, null).ToList();
                ViewBag.Dates = "No date selection";
                return View(EmpRec_Default);
            }

            return View();
        }

it hits this one when i first browse this action or run this action.

else if (DateFrom == "" && DateTo != "")

  • 2 Contributors
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  • 8 Hours Discussion Span
  • Latest Post Latest Post by JorgeM
Member Avatar for JorgeM

Null and "" is not the same.

If you are passing null values then check for nulls.

Try...

 string.IsNullOrEmpty(var1)

Which is the equivalent to...

 ((var1 == null || var1 == string.Empty))

So in your case...

 If (string.IsNullOrEmpty(DateFrom) && string.IsNullOrEmpty(DateTo))
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