Difference? myDate.Equals(Date.MinValue) -or- myDate = Date.MinValue

[Andreas Klemt]

Hello,
what is the difference and what is better (performance etc) ?

a) If myDate.Equals(Date.MinValue)
b) If myDate = Date.MinValue

Thanks,
Andreas

 

[Jerry III]

Don't know about VB but in C# the operator calls the function. Depending on
the compiler the function might be faster (but most likely it will be the
same as the compiler will do the substitution, much like inline functions in
C++).

Jerry

 

[Andreas Klemt]

Hello,

results are:

a) If myDate.Equals(Date.MinValue)
0,007439

b) If myDate = Date.MinValue
0,002253

Regards,
Andreas

 

[Natty Gur]

Take a look in IL and you will see that CLR use Boxing just for Equals.
Equals should be slower.

//000004: Dim myDate As Date
//000005: If myDate.Equals(Date.MinValue) Then
IL_0001: ldloca.s myDate
IL_0003: ldsfld valuetype [mscorlib]System.DateTime
[mscorlib]System.DateTime::MinValue
IL_0008: box [mscorlib]System.DateTime
IL_000d: call instance bool
[mscorlib]System.DateTime::Equals(object)
IL_0012: brfalse.s IL_0014
//000006:
//000007: End If
IL_0014: nop
//000008: If myDate = Date.MinValue Then
IL_0015: ldloc.0
IL_0016: ldsfld valuetype [mscorlib]System.DateTime
[mscorlib]System.DateTime::MinValue
IL_001b: call int32
[mscorlib]System.DateTime::Compare(valuetype [mscorlib]System.DateTime,

valuetype [mscorlib]System.DateTime)
IL_0020: ldc.i4.0
IL_0021: bne.un.s IL_0023
//000009:
//000010: End If

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