Check two null and eqauilty In LinQ

Question

I am not strong in LinQ So I try to check if two property is not null and one of them is equal variable number

so

public static string FilldrpRequestExecutionUnitsEmployee(int unitID)
{
    List<ApplicationStep> myAppList = 
        new ApplicationStepLogic(ApplicationType.Web)
        .GetAll()
        .Where(x => x.UnitId ==(int?) unitID && (x.UnitId && x.variable != null));
    return "";
}

please help I am linq beginner

(x.UnitId != null && x.variable != null), but you can just remove it as you're comparing to unitID which is not null — Gusman, Feb 29 '16 at 13:59
Assuming that `x.UnitId` is a `int?` then you cannot just "and" it to another `bool` value. Did you mean to use `x.UnitId.HasValue()`? — juharr, Feb 29 '16 at 14:06

score 2 · Accepted Answer · edited May 23 '17 at 11:45

2

This should do it:

....
.Where(x => x.UnitId == (int?)unitID && x.variable != null)
.ToList();

You don't need the additional null check on the UnitId nullable if you already compare it with the casted unitID-int. Nullable<T>.Equals is overridden meaningfully and is safe(no exception if it's null). Fyi:Why does the == operator work for Nullable when == is not defined?

edited May 23 '17 at 11:45

Community

1
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answered Feb 29 '16 at 13:59

Tim Schmelter

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Error 114 Cannot implicitly convert type 'System.Collections.Generic.IEnumerable' to 'System.Collections.Generic.List'. An explicit conversion exists (are you missing a cast?) – sara adly Feb 29 '16 at 14:03
@saraadly: you need to append `ToList()`. However, it's not clear how you want to convert this list into a `string` that is returned from the method. – Tim Schmelter Feb 29 '16 at 14:05

Check two null and eqauilty In LinQ

1 Answers1