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Drawing an image from a data URL to a canvas
...strDataURI;
The drawImage() method of HTML5 Canvas Context lets you copy all or a portion of an image (or canvas, or video) onto a canvas.
You might use it like so:
var myCanvas = document.getElementById('my_canvas_id');
var ctx = myCanvas.getContext('2d');
var img = new Image;
img.onload = func...
Jasmine JavaScript Testing - toBe vs toEqual
...y word for it; see the source code for toBe.
But b and c represent functionally equivalent objects; they both look like
{ foo: { bar: 'baz' } }
Wouldn't it be great if we could say that b and c are "equal" even if they don't represent the same object?
Enter toEqual, which checks "deep equality" (i....
What is the size of column of int(11) in mysql in bytes?
...e 4 bytes no matter what length is specified.
TINYINT = 1 byte (8 bit)
SMALLINT = 2 bytes (16 bit)
MEDIUMINT = 3 bytes (24 bit)
INT = 4 bytes (32 bit)
BIGINT = 8 bytes (64 bit).
The length just specifies how many characters to pad when selecting data with the mysql command line client. 12345 sto...
How to sum up an array of integers in C#
...
int sum = arr.AsParallel().Sum(); a faster version that uses multiple cores of the CPU. To avoid System.OverflowException you can use long sum = arr.AsParallel().Sum(x => (long)x); For even faster versions that avoid overflow exception and s...
Handling applicationDidBecomeActive - “How can a view controller respond to the app becoming Active?
...tionDidBecomeActiveNotification and specify which method that you want to call when that notification gets sent to your application.
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(someMethod:)
...
When to use symbols instead of strings in Ruby?
...iers. For Ruby < 2.2 only use symbols when they aren't generated dynamically, to avoid memory leaks.
Full answer
The only reason not to use them for identifiers that are generated dynamically is because of memory concerns.
This question is very common because many programming languages don't h...
Django set field value after a form is initialized
...value after the form was submitted, you can use something like:
if form.is_valid():
form.cleaned_data['Email'] = GetEmailString()
Check the referenced docs above for more on using cleaned_data
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How to get the first element of an array?
...code. It simply shows undefined, since that's the value of a[0], which actually is the first item in the array. If you want it to show foo you should skip all undefined values but it wouldn't be the first item in the array.
– Michiel van der Blonk
Sep 6 '16 at ...
Can I replace groups in Java regex?
I have this code, and I want to know, if I can replace only groups (not all pattern) in Java regex.
Code:
7 Answers
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Dictionary returning a default value if the key does not exist [duplicate]
...Value(key, out value);
and just ignore the return value. However, that really will just return default(TValue), not some custom default value (nor, more usefully, the result of executing a delegate). There's nothing more powerful built into the framework. I would suggest two extension methods:
pu...