大约有 40,000 项符合查询结果（耗时：0.0478秒） [XML]
Random color generator
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You can remove .split('') call. String already have Array indexer.
– ujeenator
Jul 27 '15 at 6:08
4
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When is std::weak_ptr useful?
...want to keep them in memory, so you hold a strong pointer to them. Periodically, you scan the cache and decide which objects have not been accessed recently. You don't need to keep those in memory, so you get rid of the strong pointer.
But what if that object is in use and some other code holds a s...
Efficient method to generate UUID String in JAVA (UUID.randomUUID().toString() without the dashes)
...y. There's an API I'm working with (high profile, well known) that doesn't allow dashes in its UUID. You have to strip them.
– Michael Gaines
Oct 28 '15 at 3:28
20
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Is it possible to roll back CREATE TABLE and ALTER TABLE statements in major SQL databases?
...cle Database 11g Release 2 and above - by default, no, but an alternative called edition-based redefinition exists
Older versions of Oracle - no; DDL causes an implicit commit
SQL Server - yes
Sybase Adaptive Server - yes
DB2 - yes
Informix - yes
Firebird (Interbase) - yes
SQLite also appears to h...
Converting NSString to NSDate (and back again)
...String = @"01-02-2010";
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:@"dd-MM-yyyy"];
NSDate *dateFromString = [dateFormatter dateFromString:dateString];
NSDate convert to NSString:
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[d...
How to determine whether an object has a given property in JavaScript
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Or even better — Object.prototype.hasOwnProperty.call(x, 'y'), so that property named "hasOwnProperty" would not conflict with inspection process ;)
– kangax
Dec 24 '09 at 14:03
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Correct way to define Python source code encoding
...f you want to be 100% python-docs-recommendation-compatible.
More specifically, you need to use whatever is recognized by Python and the specific editing software you use (if it needs/accepts anything at all). E.g. the coding form is recognized (out of the box) by GNU Emacs but not Vim (yes, withou...
Getting an “ambiguous redirect” error
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Bash can be pretty obtuse sometimes.
The following commands all return different error messages for basically the same error:
$ echo hello >
bash: syntax error near unexpected token `newline`
$ echo hello > ${NONEXISTENT}
bash: ${NONEXISTENT}: ambiguous redirect
$ echo hello ...
Send POST data on redirect with JavaScript/jQuery? [duplicate]
Basically what I want to do is send POST data when I change the window.location , as if a user has submitted a form and it went to a new page. I need to do it this way because I need to pass along a hidden URL, and I can’t simply place it in the URL as a GET for cosmetic reasons.
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How to return PDF to browser in MVC?
...e objects...
– Kobi
Feb 8 '12 at 16:32
Yes, using statements are good. If this is a production app with more than, say...