I'm doing a simple Pie chart that counts current employee, I'm still new to LINQ so I just want to ask is there a way to total count null values?
Here's my code so far:
public ActionResult PieCount()
{
int undefined = db.EMPs.Where(x => x.JS_REF == 1).Count();
int regular = db.EMPs.Where(x => x.JS_REF ==2 ).Count();
int contractual = db.EMPs.Where(x => x.JS_REF == 3).Count();
int probationary = db.EMPs.Where(x => x.JS_REF ==4 ).Count();
int notdefined = db.EMPs.Where(x => x.JS_REF == null ).Count();
Ratio obj = new Ratio();
obj.Undefined = undefined;
obj.Contractual = contractual;
obj.Regular = regular;
obj.Probationary = probationary;
obj.Notdefined = notdefined;
return Json(new { result = obj }, JsonRequestBehavior.AllowGet);
}
It's working so far but when I tried to count null value "x.JS_REF == null" I'm getting an error
here's the error: enter image description here
My database: enter image description here
Just add a predicate to your Count()
expression
int notdefined = db.EMPs.Count(x => x.JS_REF == 0);
or
int notdefined = db.EMPs.Count(x => String.IsNullOrEmpty(x.JS_REF.ToString()) == null);
Note that: int
cannot be null. If a value is not set to it, then the default value I believe is zero. So you should check your type of JS_REF
is int
or int?
Refactor code
You should get all data at one time then count from them instead of calling multiple times.
var data = db.EMPs.Where(x => 0 <= x.JS_REF && x.JS_REF <= 4).Select(p => p.JS_REF ).ToList();
int undefined = data.Count(x => x == 1);
int regular = ddata.Count(x => x == 2);
int contractual = data.Count(x => x == 3);
int probationary = data.Count(x => x == 4);
int notdefined = data.Count(x => x == 0);
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