大约有 35,487 项符合查询结果(耗时:0.1084秒) [XML]

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Difference between IsNullOrEmpty and IsNullOrWhiteSpace in C# [duplicate]

... 190 Source: MSDN IsNullOrWhiteSpace is a convenience method that is similar to the following...
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Measure the time it takes to execute a t-sql query

I have two t-sql queries using SqlServer 2005. How can I measure how long it takes for each one to run? 6 Answers ...
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Calculate the execution time of a method

...me to measure time execution in .NET. UPDATE: As pointed out by @series0ne in the comments section: If you want a real precise measurement of the execution of some code, you will have to use the performance counters that's built into the operating system. The following answer contains a nice ove...
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Is there a function to make a copy of a PHP array to another?

... $a = array(); $b = $a; $b['foo'] = 42; var_dump($a); Will yield: array(0) { } Whereas: $a = new StdClass(); $b = $a; $b->foo = 42; var_dump($a); Yields: object(stdClass)#1 (1) { ["foo"]=> int(42) } You could get confused by intricacies such as ArrayObject, which is an object th...
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Only read selected columns

...NULL", 6)), + header = TRUE) Year Jan Feb Mar Apr May Jun 1 2009 -41 -27 -25 -31 -31 -39 2 2010 -41 -27 -25 -31 -31 -39 3 2011 -21 -27 -2 -6 -10 -32 Change "integer" to one of the accepted types as detailed in ?read.table depending on the real type of data. data.txt looks like thi...
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Is the primary key automatically indexed in MySQL?

... | edited Dec 3 '11 at 20:41 answered Jul 1 '09 at 20:24 ...
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Should I use a class or dictionary?

... answered Oct 28 '10 at 17:18 adwadw 4,2532020 silver badges1818 bronze badges ...
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CSS vertical alignment text inside li

... 101 Define the parent with display: table and the element itself with vertical-align: middle and di...
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Abstract Class vs Interface in C++ [duplicate]

...for proper cleanup virtual ~MyInterface() {} virtual void Method1() = 0; virtual void Method2() = 0; }; class MyAbstractClass { public: virtual ~MyAbstractClass(); virtual void Method1(); virtual void Method2(); void Method3(); virtual void Method4() = 0; // make MyAbstractClass...
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Convert objective-c typedef to its string equivalent

...he classic C way is dangerous if your enum values are not continguous from 0). Something like this would work: - (NSString*)formatTypeToString:(FormatType)formatType { NSString *result = nil; switch(formatType) { case JSON: result = @"JSON"; break; c...