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Should I use px or rem value units in my CSS? [closed]
...ortant to know that per spec, the CSS px unit does not equal one physical display pixel. This has always been true – even in the 1996 CSS 1 spec.
CSS defines the reference pixel, which measures the size of a pixel on a 96 dpi display. On a display that has a dpi substantially different than 96d...
Difference between onStart() and onResume()
...t get the meaning of onStart() transition state. The onResume() method is always called after onStart() . Why can't it be the onResume() is invoked after onRestart() and onCreate() methods just excluding onStart() ? What is its purpose?
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Determine if variable is defined in Python [duplicate]
...er a variable has been set at a particular place in the code at runtime? This is not always obvious because (1) the variable could be conditionally set, and (2) the variable could be conditionally deleted. I'm looking for something like defined() in Perl or isset() in PHP or defined? in Ruby.
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Hibernate vs JPA vs JDO - pros and cons of each? [closed]
...otes:
JDO and JPA are both specifications, not implementations.
The idea is you can swap JPA implementations, if you restrict your code to use standard JPA only. (Ditto for JDO.)
Hibernate can be used as one such implementation of JPA.
However, Hibernate provides a native API, with features above...
What is state-of-the-art for text rendering in OpenGL as of version 4.1? [closed]
...ixel shader instead, these suffer from not being easily antialiased, which is trivial using a distance-map-textured quad, and evaluating curves in the shader is still computationally much more expensive than necessary.
The best trade-off between "fast" and "quality" are still textured quads with a ...
Entity Framework: There is already an open DataReader associated with this Command
I am using Entity Framework and occasionally i will get this error.
17 Answers
17
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Find out whether radio button is checked with JQuery?
I can set a radio button to checked fine, but what I want to do is setup a sort of 'listener' that activates when a certain radio button is checked.
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Why does the indexing start with zero in 'C'?
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In C, the name of an array is essentially a pointer [but see the comments], a reference to a memory location, and so the expression array[n] refers to a memory location n elements away from the starting element. This means that the index is used as an ...
php is null or empty?
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What you're looking for is:
if($variable === NULL) {...}
Note the ===.
When use ==, as you did, PHP treats NULL, false, 0, the empty string, and empty arrays as equal.
sh...