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LINQ - Left Join, Group By, and Count
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from p in context.ParentTable
join c in context.ChildTable on p.ParentId equals c.ChildParentId into j1
from j2 in j1.DefaultIfEmpty()
group j2 by p.ParentId into grouped
select new { ParentId = grouped.Key, Count = grouped.Count(t=>t.ChildId != nu...
Get operating system info
I recently started wondering about sites like http://thismachine.info/ that get the user's operating system info. I have not been able to find out how to do that with PHP, and wanted to try to figure it out.
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What is the purpose of setting a key in data.table?
I am using data.table and there are many functions which require me to set a key (e.g. X[Y] ). As such, I wish to understand what a key does in order to properly set keys in my data tables.
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Debug Error \"pure virtual function call\" 原因解析 - 更多技术 - 清泛...
Debug Error "pure virtual function call" 原因解析结论：一般在构造、析构函数中调用虚函数就可能出这个错误，检查纯虚函数，看看有没有在构造析构函数中调用。以下来自：http: www.kuqin.c...结论：一般在构造、析构函数中调用虚函数...
Dark theme in Netbeans 7 or 8
Is there a way to have a dark theme in Netbeans?
6 Answers
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Get list of passed arguments in Windows batch script (.bat)
I'd like to find a Windows batch counterpart to Bash's $@ that holds a list of all arguments passed into a script.
14 An...
CSS disable text selection
Currently, I have put this in the body tag to disable text selections:
9 Answers
9
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Display a float with two decimal places in Python
...0'
The result of the operator is a string, so you can store it in a variable, print etc.
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What's the difference between “groups” and “captures” in .NET regular expressions?
I'm a little fuzzy on what the difference between a "group" and a "capture" are when it comes to .NET's regular expression language. Consider the following C# code:
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Java - sending HTTP parameters via POST method easily
... sent as part of the URL.
In a POST request, the parameters are sent as a body of the request, after the headers.
To do a POST with HttpURLConnection, you need to write the parameters to the connection after you have opened the connection.
This code should get you started:
String urlParameters ...