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Unable to Cast from Parent Class to Child Class
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A simple way to downcast in C# is to serialize the parent and then deserialize it into the child.
var serializedParent = JsonConvert.SerializeObject(parentInstance);
Child c = JsonConvert.DeserializeObject<Child>(serializedParent);
I have a si...
Evaluate expression given as a string
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The eval() function evaluates an expression, but "5+5" is a string, not an expression. Use parse() with text=<string> to change the string into an expression:
> eval(parse(text="5+5"))
[1] 10
> class("5+5")
[1] "character"
> class(parse(text="5+5"))
[1] "expressio...
Comparing strings with == which are declared final in Java
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When you declare a String (which is immutable) variable as final, and initialize it with a compile-time constant expression, it also becomes a compile-time constant expression, and its value is inlined by the compiler where it is used. So, in your second cod...
Can you control how an SVG's stroke-width is drawn?
Currently building a browser-based SVG application. Within this app, various shapes can be styled and positioned by the user, including rectangles.
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What is the difference between static_cast and C style casting?
Is there any reason to prefer static_cast<> over C style casting? Are they equivalent? Is their any sort of speed difference?
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Best way to allow plugins for a PHP application
I am starting a new web application in PHP and this time around I want to create something that people can extend by using a plugin interface.
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What is the fastest or most elegant way to compute a set difference using Javascript arrays?
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if don't know if this is most effective, but perhaps the shortest
A = [1, 2, 3, 4];
B = [1, 3, 4, 7];
diff = A.filter(function(x) { return B.indexOf(x) < 0 })
console.log(diff);
Updated to ES6:
A = [1, 2, 3, 4];
B = [1, 3, 4, 7];
diff...
How to grant permission to users for a directory using command line in Windows?
How can I grant permissions to a user on a directory (Read, Write, Modify) using the Windows command line?
17 Answers
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Difference between a Structure and a Union
Is there any good example to give the difference between a struct and a union ?
Basically I know that struct uses all the memory of its member and union uses the largest members memory space. Is there any other OS level difference?
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Best way to get child nodes
...iety of methods to get the first child element from any element, but which is the best? By best, I mean: most cross-browser compatible, fastest, most comprehensive and predictable when it comes to behaviour. A list of methods/properties I use as aliases:
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