What is fastest: (int), Convert.ToInt32(x) or Int32.Parse(x)?

Question

Which of the following code is fastest/best practice for converting some object x?

int myInt = (int)x;

or

int myInt = Convert.T         


        

Answer 1

If you know that the data is definitely int then int myInt = (int)x; should be the fastest option. Otherwise TryParse will help you to get it right without the slowness of exceptions.

BTW :

(int) only unboxes therefore faster,

(int) IL =

  .locals init (
        [0] object x,
        [1] int32 Y)
    L_0000: ldc.i4.1 
    L_0001: box int32
    L_0006: stloc.0 
    L_0007: ldloc.0 
    L_0008: unbox int32
    L_000d: ldobj int32
    L_0012: stloc.1 
    L_0013: ret 

Convert.Toint32=

.locals init (
        [0] object x,
        [1] int32 Y)
    L_0000: ldc.i4.1 
    L_0001: box int32
    L_0006: stloc.0 
    L_0007: ldloc.0 
    L_0008: call object [mscorlib]System.Runtime.CompilerServices.RuntimeHelpers::GetObjectValue(object)
    L_000d: call int32 [mscorlib]System.Convert::ToInt32(object)
    L_0012: stloc.1 
    L_0013: ret