大约有 43,000 项符合查询结果(耗时:0.0436秒) [XML]

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How do I implement an Objective-C singleton that is compatible with ARC?

How do I convert (or create) a singleton class that compiles and behaves correctly when using automatic reference counting (ARC) in Xcode 4.2? ...
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How do you find out the type of an object (in Swift)?

...ped optionals! i.e. var myVar: SomeType!. Compiler gives the error "Cannot convert value of type 'SomeType!.Type' (aka 'ImplicitlyUnwrappedOptional<SomeType>.Type') to expected argument type 'AnyClass' (aka 'AnyObject.Type') Compiler suggest adding as! AnyClass after the type but then program...
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Exception 'open failed: EACCES (Permission denied)' on Android

...wrong place. This is right: <manifest> <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/> ... <application> ... <activity> ... </activity> </application&gt...
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How to get the first five character of a String

...get the result back in string then you can use: Using String Constructor and LINQ's Take string firstFivChar = new string(yourStringVariable.Take(5).ToArray()); The plus with the approach is not checking for length before hand. The other way is to use String.Substring with error checking ...
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What is the most appropriate way to store user settings in Android application

...eating an application which connects to the server using username/password and I would like to enable the option "Save password" so the user wouldn't have to type the password each time the application starts. ...
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Are nested try/except blocks in python a good programming practice?

...more complicated situations you may be right, but I think that when you're converting between exception types you often know that the details of the first exception don't matter to the outside user. That is, if __getattr__ raises an exception the bug is probably a typo in the attribute access, not a...
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With MySQL, how can I generate a column containing the record index in a table?

...rt allows the variable initialization without requiring a separate SET command. Test case: CREATE TABLE league_girl (position int, username varchar(10), score int); INSERT INTO league_girl VALUES (1, 'a', 10); INSERT INTO league_girl VALUES (2, 'b', 25); INSERT INTO league_girl VALUES (3, 'c', 75)...
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“for loop” with two variables? [duplicate]

...other set (Note that if your lists contains other lists, you might want to convert the inner lists to tuples first so that they are hashable; otherwise the call to set will fail.). The list function then turns the set back into a list. UPDATE 2 OR, the OP might want elements that are identical in...
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How to get week number in Python?

... This approach is better in cases where you don't want to split or convert a date which comes as a string... just pass the string in strptime in string format as it is and specify the format in second argument. Good solution. Remember: %W if week starts on Mondays. – Th...
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Jackson Vs. Gson [closed]

...ns of Gson also include streaming reader Tree model (DOM-like access); can convert between various models (tree <-> java object <-> stream) Can use any constructors (or static factory methods), not just default constructor Field and getter/setter access (earlier gson versions only used f...