Create Managed Array with long/size_t length
c++-cli
Solution
Managed arrays are implemented for using `Int32` as indices, there is no way around that. You cannot allocate arrays larger than `Int32.MaxValue`.
You could use the static method `Array::CreateInstance` (the overload that takes a `Type` and an array of `Int64`), and then cast the resulting `System::Array` to the appropriate actual array type (e.g. `array<int>^`). Note that the passed values must not be larger than `Int32.MaxValue`. And you would still need to cast.
So you have at least two options. Either casting:
// Would truncate the value if it is too large
array<int>^ a = gcnew array<int>((int)len);
or this (no need to cast len, but the result of `CreateInstance`):
// Throws an ArgumentOutOfRangeException if len is too large
array<int>^ a = (array<int>^)Array::CreateInstance(int::typeid, len);
Personally, i find the first better. You still might want to check the actual size of len so that you don't run into any of the mentioned errors.
Problem
Jumping straight to code, this is what I would like to do: ``` size_t len = obj->someLengthFunctionThatReturnsTypeSizeT(); array<int>^ a = gcnew array<int>(len); ``` When I try this, I get the error conversion from size_t to int, possible loss of data Is there a way I can get this code to compile without explicitly casting to int? I find it odd that I can't initialize an array to this size, especially because there is a LongLength property (and how could you get a length as a long - bigger than int - if you can only initialize a length as an int?). Thanks! P.S.: I did find this article that says that it may be impractical to allocate an array that is truly size_t, but I don't think that is a concern. The point is that the length I would like to initialize to is stored in a size_t variable.