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Object-orientation in C
...be an instance of the superclass, and then you can cast around pointers to base and derived classes freely:
struct base
{
/* base class members */
};
struct derived
{
struct base super;
/* derived class members */
};
struct derived d;
struct base *base_ptr = (struct base *)&d; //...
Convert blob to base64
This is a snippet for the code that I want to do Blob to Base64 string:
9 Answers
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Decode Base64 data in Java
I have an image that is Base64 encoded. What is the best way to decode that in Java? Hopefully using only the libraries included with Sun Java 6.
...
Quickest way to convert a base 10 number to any base in .NET?
... and old(ish) C# method I wrote that takes a number and converts it to any base:
12 Answers
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Why do we use Base64?
...
Your first mistake is thinking that ASCII encoding and Base64 encoding are interchangeable. They are not. They are used for different purposes.
When you encode text in ASCII, you start with a text string and convert it to a sequence of bytes.
When you encode data in Base64, you...
C++ templates that accept only certain types
...
I suggest using Boost's static assert feature in concert with is_base_of from the Boost Type Traits library:
template<typename T>
class ObservableList {
BOOST_STATIC_ASSERT((is_base_of<List, T>::value)); //Yes, the double parentheses are needed, otherwise the comma will be...
Round to 5 (or other number) in Python
...ndard function in Python, but this works for me:
Python 2
def myround(x, base=5):
return int(base * round(float(x)/base))
Python3
def myround(x, base=5):
return base * round(x/base)
It is easy to see why the above works. You want to make sure that your number divided by 5 is an integ...
Algorithms based on number base systems? [closed]
I've noticed recently that there are a great many algorithms out there based in part or in whole on clever uses of numbers in creative bases. For example:
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new keyword in method signature
...:
You cannot override a non-virtual or
static method. The overridden base
method must be virtual, abstract, or
override.
So the 'new' keyword is needed to allow you to 'override' non-virtual and static methods.
s...
Downcasting shared_ptr to shared_ptr?
...amic_pointer_cast. It is supported by std::shared_ptr.
std::shared_ptr<Base> base (new Derived());
std::shared_ptr<Derived> derived =
std::dynamic_pointer_cast<Derived> (base);
Documentation: https://en.cppreference.com/w/cpp/memory/shared_ptr/pointer_cast
Also, ...