大约有 47,000 项符合查询结果(耗时:0.0540秒) [XML]

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How to do ToString for a possibly null object?

... C# 6.0 Edit: With C# 6.0 we can now have a succinct, cast-free version of the orignal method: string s = myObj?.ToString() ?? ""; Or even using interpolation: string s = $"{myObj}"; Original Answer: string s = (myObj ?? String.Empty).ToString(); or strin...
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Using two values for one switch case statement

... oh ok. That was easy. Didn't know I could do that – Ankush May 23 '13 at 6:14 18 ...
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How to get cumulative sum

...ata --> Create Table CUMULATIVESUM (id tinyint , SomeValue tinyint) **Now let put some data in the table** Insert Into CUMULATIVESUM Select 1, 10 union Select 2, 2 union Select 3, 6 union Select 4, 10 here I am joining same table (SELF Joining) Select c1.ID, c1.SomeValue, c2.SomeValue ...
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Gem::LoadError for mysql2 gem, but it's already in Gemfile

...e with a specific mysql version like below gem 'mysql2', '~> 0.3.18' Now stop the server and run bundle bundle install Now restart your server. It should work. rails s share | improve thi...
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Getting all names in an enum as a String[]

...and way to lazy to create an State array i guess, hehe, anyways iedited it now :) – PermGenError Dec 9 '12 at 0:15 2 ...
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Covariance and contravariance real world example

...e donkey gobbling code last week and i was so glad that we have covariance now. :-) – Eric Lippert Apr 18 '10 at 15:26 ...
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Get model's fields in Django

... Thank you Will. Good to know that other people are using _meta as well. I like the idea of having a wrapper function. Lazerscience, thank you also. Good to know there is a nice method to get the many_to_many fields. Joe – Joe...
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Real life example, when to use OUTER / CROSS APPLY in SQL

... @mr_eclair looks like it is now at itprotoday.com/software-development/… – Martin Smith May 19 '18 at 10:22 ...
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Traits in PHP – any real world examples/best practices? [closed]

Traits have been one of the biggest additions for PHP 5.4. I know the syntax and understand the idea behind traits, like horizontal code re-use for common stuff like logging, security, caching etc. ...
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Setting Environment Variables for Node to retrieve

...ID and USER_KEY from either process.env or some specificed file on disk. Now, the magic happens when you run the application. USER_ID=239482 USER_KEY=foobar node app.js That will pass the user id 239482 and the user key as foobar. This is suitable for testing, however for production, you will pr...