大约有 42,000 项符合查询结果(耗时:0.0472秒) [XML]

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Constructors vs Factory Methods [closed]

...ns: Elements of Reusable Object-Oriented Software by Gamma, Helm, Johnson, and Vlissides. Use the Factory Method pattern when a class can't anticipate the class of objects it must create a class wants its subclasses to specify the objects it creates classes delegate responsibility to one of sever...
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How do I unload (reload) a Python module?

I have a long-running Python server and would like to be able to upgrade a service without restarting the server. What's the best way do do this? ...
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How to check for an undefined or null variable in JavaScript?

...xistingObj.someUndefProperty. An undefined property doesn't yield an error and simply returns undefined, which, when converted to a boolean, evaluates to false. So, if you don't care about 0 and false, using if(obj.undefProp) is ok. There's a common idiom based on this fact: value = obj.prop || de...
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How do I send a POST request with PHP?

... when it is done. The problem is that the URL only accepts POST methods, and it does not take any action with GET method... ...
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Replace console output in Python

... An easy solution is just writing "\r" before the string and not adding a newline; if the string never gets shorter this is sufficient... sys.stdout.write("\rDoing thing %i" % i) sys.stdout.flush() Slightly more sophisticated is a progress bar... this is something I am using: d...
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Android: How to stretch an image to the screen width while maintaining aspect ratio?

...to download an image (of unknown size, but which is always roughly square) and display it so that it fills the screen horizontally, and stretches vertically to maintain the aspect ratio of the image, on any screen size. Here is my (non-working) code. It stretches the image horizontally, but not vert...
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How do you performance test JavaScript code?

...e user/client. For example, we had a project with an Ext accordion that expanded to show some data and then a few nested Ext grids. Everything was actually rendering pretty fast, no single operation took a long time, there was just a lot of information being rendered all at once, so it felt slow to...
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How to use sed to replace only the first occurrence in a file?

...r if you prefer' solution. It would also be good to explain the answers - and to make the answer address the question directly, and then generalize, rather than generalize only. But good answer. – Jonathan Leffler Sep 29 '08 at 13:15 ...
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How can I improve my paw detection?

...ghtly more work. The two animations below show your "Overlapping Paws" and "Grouped Paws" example data. This method seems to be working perfectly. (And for whatever it's worth, this runs much more smoothly than the GIF images below on my machine, so the paw detection algorithm is fairly fast......
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Encode URL in JavaScript?

... Check out the built-in function encodeURIComponent(str) and encodeURI(str). In your case, this should work: var myOtherUrl = "http://example.com/index.html?url=" + encodeURIComponent(myUrl); shar...