大约有 40,000 项符合查询结果(耗时:0.0464秒) [XML]

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What is a regular expression for a MAC Address?

...at" comes from Wikipedia, not the 802.3 standards body. IEEE 802-2014 actually specifies hyphens for ordinary MAC addresses (§ 8.1 ¶ 3) and colons for the obsolescent bit-reversed notation (¶ 4). Importantly, in practice, no one observes this. We simply use one or the other, but never mix them...
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Getter and Setter declaration in .NET [duplicate]

... a plain field: public string MyField But this field can be accessed by all outside users of your class. People can insert illegal values or change the value in ways you didn't expect. By using a property, you can encapsulate the way your data is accessed. C# has a nice syntax for turning a fiel...
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Viewing all defined variables [duplicate]

...ython shell. What I want to have is Matlab style listout where you can see all the variables that have been defined up to a point (so I know which names I've used, their values and such). ...
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Is there a simple way to convert C++ enum to string?

... +1, GCCXML looks very nice! (Although I almost -1ed as I initially misread this as a suggestion to use the above verbose XML syntax to encode your enum -- a solution which reeks of overengineering!) – j_random_hacker Mar 12 '09 at 9:46 ...
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How to read if a checkbox is checked in PHP?

... this is the really good form to do this in pure simple php. but have to note that the value of a checkbox is string on when it is activated an a inexisting value if it is checked. – Elvis Technologies ...
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Get model's fields in Django

Given a Django model, I'm trying to list all of its fields. I've seen some examples of doing this using the _meta model attribute, but doesn't the underscore in front of meta indicate that the _meta attribute is a private attribute and shouldn't be accessed directly? ... Because, for example, the ...
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How do I search for an object by its ObjectId in the mongo console?

... Not strange at all, people do this all the time. Make sure the collection name is correct (case matters) and that the ObjectId is exact. Documentation is here > db.test.insert({x: 1}) > db.test.find() ...
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How can I prevent SQL injection in PHP?

...is way it is impossible for an attacker to inject malicious SQL. You basically have two options to achieve this: Using PDO (for any supported database driver): $stmt = $pdo->prepare('SELECT * FROM employees WHERE name = :name'); $stmt->execute([ 'name' => $name ]); foreach ($stmt as $...
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Rspec doesn't see my model Class. uninitialized constant error

... Your spec_helper file is missing some important commands. Specifically, it's not including config/environment and initializing rspec-rails. You can add the following lines to the start of your spec/spec_helper.rb file ENV["RAILS_ENV"] ||= 'test' require File.expand_path("../../config/envi...
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What is the use of static variable in C#? When to use it? Why can't I declare the static variable in

... A static variable shares the value of it among all instances of the class. Example without declaring it static: public class Variable { public int i = 5; public void test() { i = i + 5; Console.WriteLine(i); } } public class Exercise { ...