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How to check if an object is nullable?
...pe if boxed, but you can with generics:
- so how about below. This is actually testing type T, but using the obj parameter purely for generic type inference (to make it easy to call) - it would work almost identically without the obj param, though.
static bool IsNullable<T>(T obj)
{
if (...
How to set java_home on Windows 7?
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Find JDK Installation Directory
First you need to know the installation path for the Java Development Kit.
Open the default installation path for the JDK:
C:\Program Files\Java
There should be a subdirectory like:
C:\Program Files\J...
How can I find the first occurrence of a sub-string in a python string?
... knowledge: rfind and rindex:
In general, find and index return the smallest index where the passed-in string starts, and rfind and rindex return the largest index where it starts
Most of the string searching algorithms search from left to right, so functions starting with r indicate that the...
T-SQL split string
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Thanks a lot Andy. I made a small enhancement to your script to allow the function to return an item at a specific index in the split string. It is useful only in situations when you the structure of the column one is parsing. gist.github.com/klimaye/8147...
What does @@variable mean in Ruby?
...the classes; setting the value in an instance of one changes the value for all other instances of that class and even child classes, where a variable named @shared, with one @, would not be.
[Update]
As Phrogz mentions in the comments, it's a common idiom in Ruby to track class-level data with an ...
Unable to cast object of type 'System.DBNull' to type 'System.String`
...mber.ToString()
EDIT: Haven't paid attention to ExecuteScalar. It does really return null if the field is absent in the return result. So use instead:
return (accountNumber == null) ? string.Empty : accountNumber.ToString()
...
Xcode 4 - “Archive” is greyed out?
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Ralph BRalph B
1,67322 gold badges1111 silver badges1313 bronze badges
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How to check if IEnumerable is null or empty?
... love string.IsNullOrEmpty method. I'd love to have something that would allow the same functionality for IEnumerable. Is there such? Maybe some collection helper class? The reason I am asking is that in if statements the code looks cluttered if the patter is (mylist != null && mylist.A...
How to set breakpoints on future shared libraries with a command flag
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answered Sep 19 '08 at 8:32
Shlomi FishShlomi Fish
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Understanding NSRunLoop
... run loop directly, though there are some (networking) components that may allow you to specify which run loop they will use for I/O processing.
A run loop for a given thread will wait until one or more of its input sources has some data or event, then fire the appropriate input handler(s) to proce...