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How do I select a random value from an enumeration?

... Use Enum.GetValues to retrieve an array of all values. Then select a random array item. static Random _R = new Random (); static T RandomEnumValue<T> () { var v = Enum.GetValues (typeof (T)); return (T) v.GetValue (_R.Next(v.Length)); } Test: for (in...
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KIO4_Gradient 拓展:布局中的颜色渐变 - App Inventor 2 中文网 - 清泛IT...

http://kio4.com/appinventor/287_extension_gradiente_color.htm - 让我们看一下在布局中制作颜色渐变的扩展。- 我们放置一个布局,然后在该扩展的块中插入该布局的名称,放置一个包含所需颜色的列表,以及一个从 1 到 8 的数字,用于表示...
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Group by multiple columns in dplyr, using string vector input

... Does the call to one_of() do anything here? I think it is redundant in this context, as the expression is wrapped in a call to vars(). – knowah Aug 15 '19 at 14:13 ...
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Passing an integer by reference in Python

...d you can't just assign the "variable" a new value because then you're actually creating a new object (which is distinct from the old one) and giving it the name that the old object had in the local namespace. Usually the workaround is to simply return the object that you want: def multiply_by_2(x...
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Namespace not recognized (even though it is there)

... page. This is a problem in Visual Studio (I would even go so far as to call it a bug). AutoMapper requires assemblies that are excluded from the .NET Framework 4 Client Profile. Since your project is using that version of the framework it breaks. A similar error will propagate to the build pro...
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Python None comparison: should I use “is” or ==?

...ject None, so when you do my_var is None, you're checking whether they actually are the same object (not just equivalent objects) In other words, == is a check for equivalence (which is defined from object to object) whereas is checks for object identity: lst = [1,2,3] lst == lst[:] # This is Tr...
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How to check if an email address exists without sending an email?

...here are two methods you can sometimes use to determine if a recipient actually exists: You can connect to the server, and issue a VRFY command. Very few servers support this command, but it is intended for exactly this. If the server responds with a 2.0.0 DSN, the user exists. VRFY user You can...
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What's the (hidden) cost of Scala's lazy val?

...nswered Jun 15 '10 at 7:51 oxbow_lakesoxbow_lakes 127k5252 gold badges305305 silver badges442442 bronze badges ...
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6个变态的C语言Hello World程序 - 创意 - 清泛网 - 专注C/C++及内核技术

...要动用C++的编译器g++才能编程通过。 hello1.c #define _________ } #define ________ putchar #define _______ main #define _(a) ________(a); #define ______ _______(){ #define __ ______ _(0x48)_(0x65)_(0x6C)_(0x6C) #define ___ _(0x6F)_(0x2C)_(0x20)_(0x77)_(0x6F) #define ____ _...
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How do I size a UITextView to its content?

... Tested on iOS 7 to resize an UITextView into an UITableViewCell. Works really great. This is the only answer that finally worked for me. Thanks! – Alex Nov 30 '13 at 18:40 39 ...