大约有 30,000 项符合查询结果(耗时:0.0489秒) [XML]

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Why use String.Format? [duplicate]

Why would anyone use String.Format in C# and VB .NET as opposed to the concatenation operators ( & in VB, and + in C#)? ...
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How can I drop all the tables in a PostgreSQL database?

...en create) used to work on PostgreSQL 9.1. After upgrading to 9.3, the two extra grant is necessary. – Jinghao Shi Sep 15 '14 at 23:42 4 ...
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Specifying an Index (Non-Unique Key) Using JPA

...lass Region{ @Column(name = "iso_code", nullable = false) private String isoCode; @Column(name = "name", nullable = false) private String name; } Update: If you ever need to create and index with two or more columns you may use commas. For example: @Entity @Table(name = "co...
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Best architectural approaches for building iOS networking applications (REST clients)

...t for particular service classes, but if you ,for some reasons, don't want extra copies or you are sure that you always will use one particular instance (without customisations) of the APIClient - make it a singleton, but DON'T, please DON'T make service classes as singletons. Then each view contr...
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How can I append a string to an existing field in MySQL?

... You need to use the CONCAT() function in MySQL for string concatenation: UPDATE categories SET code = CONCAT(code, '_standard') WHERE id = 1; share | improve this answer ...
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Microsecond timing in JavaScript

... more than 1,000 attempts. Only when I'm trying to do things like load an extra web page, or other, the millisecond accuracy degrades (And I'm able to successfully catch my own degraded accuracy by doing a before-and-after time check, to see if my processing time suddenly lengthened to 1 or more mi...
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Are there strongly-typed collections in Objective-C?

...will generate compiler warnings if there is a type mismatch. NSArray<NSString*>* arr = @[@"str"]; NSString* string = [arr objectAtIndex:0]; NSNumber* number = [arr objectAtIndex:0]; // Warning: Incompatible pointer types initializing 'NSNumber *' with an expression of type 'NSString *' And...
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Show the progress of a Python multiprocessing pool imap_unordered call?

... @WakanTanka: It goes in the main script after it spins off the extra threads. In my original example, it goes in the "while" loop, where rs has already launched the other threads. – MidnightLightning Aug 24 '15 at 11:58 ...
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Is it possible to get element from HashMap by its position?

...rieve by position, convert the values into an ArrayList. LinkedHashMap<String,String> linkedHashMap = new LinkedHashMap<String,String>(); /* Populate */ linkedHashMap.put("key0","value0"); linkedHashMap.put("key1","value1"); linkedHashMap.put("key2","value2"); /* Get by position */ int ...
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“is” operator behaves unexpectedly with integers

... This can be a very fast check relative to say, checking if two very long strings are equal in value. But since it applies to the uniqueness of the object, we thus have limited use-cases for it. In fact, we mostly want to use it to check for None, which is a singleton (a sole instance existing in o...