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Identify if a string is a number
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int n;
bool isNumeric = int.TryParse("123", out n);
Update As of C# 7:
var isNumeric = int.TryParse("123", out int n);
or if you don't need the number you can discard the out parameter
var isNumeric = int.TryParse("123", out _);
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Drop unused factor levels in a subsetted data frame
I have a data frame containing a factor . When I create a subset of this dataframe using subset or another indexing function, a new data frame is created. However, the factor variable retains all of its original levels, even when/if they do not exist in the new dataframe.
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Tab space instead of multiple non-breaking spaces (“nbsp”)?
Is it possible to insert a tab character in HTML instead of having to type   four times?
35 Answers
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What are allowed characters in cookies?
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this one's a quickie:
You might think it should be, but really it's not at all!
What are the allowed characters in both cookie name and value?
According to the ancient Netscape cookie_spec the entire NAME=VALUE string i...
How to construct a REST API that takes an array of id's for the resources
...uilding a REST API for my project. The API for getting a given user's INFO is:
5 Answers
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What is the difference between IEnumerator and IEnumerable? [duplicate]
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IEnumerable is an interface that defines one method GetEnumerator which returns an IEnumerator interface, this in turn allows readonly access to a collection. A collection that implements IEnumerable can be used with a foreach statement....
Pass data to layout that are common to all pages
I have a website which have a layout page. However this layout page have data which all pages model must provide such page title, page name and the location where we actually are for an HTML helper I did which perform some action. Also each page have their own view models properties.
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Why are exclamation marks used in Ruby methods?
...? ) that ask a question like include? that ask if the object in question is included, this then returns a true/false.
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How to use if-else option in JSTL
Is there an if-else tag available in JSTL?
6 Answers
6
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Does a const reference class member prolong the life of a temporary?
Why does this:
5 Answers
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