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How To Save Canvas As An Image With canvas.toDataURL()?
I'm currently building a HTML5 web app/Phonegap native app and I can't seem to figure out how to save my canvas as an image with canvas.toDataURL() . Can somebody help me out?
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Select distinct values from a table field
...ant any ordering to be applied to a query, not even the default ordering, call order_by() with no parameters.
and distinct() in the note where it discusses issues with using distinct() with ordering.
To query your DB, you just have to call:
models.Shop.objects.order_by().values('city').distinct(...
Difference between global and device functions
Can anyone describe the differences between __global__ and __device__ ?
9 Answers
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Ruby on Rails: Delete multiple hash keys
...re unaware of the Hash#except method ActiveSupport adds to Hash.
It would allow your code to be simplified to:
redirect_to my_path(params.except(:controller, :action, :other_key))
Also, you wouldn't have to monkey patch, since the Rails team did it for you!
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What are the rules for calling the superclass constructor?
What are the C++ rules for calling the superclass constructor from a subclass one?
10 Answers
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C++及Windows异常处理(try，catch; __try,__finally, __except) - C/C++ - ...
C++及Windows异常处理(try，catch; __try,__finally, __except)C++及Windows异常处理(try，catch; __try,__finally; __try, __except)一道笔试题引起的探究题目：
int* p = 0x00000000; // pointer to NULL
puts( "hello ");
__try{
puts( "in try ...
Keyboard shortcuts in WPF
I know about using _ instead of & , but I'm looking at all the Ctrl + type shortcuts.
10 Answers
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How is __eq__ handled in Python and in what order?
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The a == b expression invokes A.__eq__, since it exists. Its code includes self.value == other. Since int's don't know how to compare themselves to B's, Python tries invoking B.__eq__ to see if it knows how to compare itself to an int.
If you amend your ...
REST APIs: custom HTTP headers vs URL parameters
...A mobile platform should almost always be the User himself acting, and use appropriate first person credentials for the transaction.
– Nialscorva
Feb 15 '12 at 0:08
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Not showing placeholder for input type=“date” field
I am doing a phonegap app. When I am trying type="date" input field as shown below, it shows date picker in iPhone as I expected but it doesn't show the placeholder I have given. I found the same issue here in SO, but no solution anywhere.
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