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How to detect if multiple keys are pressed at once using JavaScript?
...g for optimization. This is because the script tag blocks further elements from loading until its script is finished downloading. Putting it ahead of the content allows the content to load beforehand.
B (which is where your interest lies) You can check for one or more keys at a time where /*insert c...
vbscript output to console
...pts and Code Repository.
You can do this with the following and stay away from the cscript/wscript differences and allows you to get the same console output that a batch file would have. This can help if your calling VBS from a batch file and need to make it look seamless.
Set fso = CreateObject ...
How can I listen to the form submit event in javascript?
...documentation on MDN.
To cancel the native submit event (prevent the form from being submitted), use .preventDefault() in your callback function,
document.querySelector("#myForm").addEventListener("submit", function(e){
if(!isValid){
e.preventDefault(); //stop form from submitting
...
What's the algorithm to calculate aspect ratio?
...ich shows one way to detect the screen size and calculate the aspect ratio from that. This works in FF3, I'm unsure what support other browsers have for screen.width and screen.height.
<html><body>
<script type="text/javascript">
function gcd (a, b) {
retur...
How do you represent a graph in Haskell?
...rted to additional indirection, as you're suggesting; often by using a map from ids to the actual elements, and having elements contain references to the ids instead of to other elements. The main thing I didn't like about doing that (aside from the obvious inefficiency) is that it felt more fragile...
Why is it necessary to set the prototype constructor?
...cause (without explicit checks), we'd have no way to return a Student copy from the "base" class. We can only return a Person. However, if we had reset the constructor:
// correct the constructor pointer because it points to Person
Student.prototype.constructor = Student;
...then everything wor...
Is it a good practice to use try-except-else in Python?
From time to time in Python, I see the block:
10 Answers
10
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C# namespace alias - what's the point?
...ith extern aliases for using types with the same fully-qualified type name from different assemblies - rare, but useful to be supported.
Actually, I can see another use: when you want quick access to a type, but don't want to use a regular using because you can't import some conflicting extension...
Erasing elements from a vector
I want to clear a element from a vector using the erase method. But the problem here is that the element is not guaranteed to occur only once in the vector. It may be present multiple times and I need to clear all of them. My code is something like this:
...
How do I resize an image using PIL and maintain its aspect ratio?
...ethod to do this: the method Image.thumbnail.
Below is an (edited) example from the PIL documentation.
import os, sys
import Image
size = 128, 128
for infile in sys.argv[1:]:
outfile = os.path.splitext(infile)[0] + ".thumbnail"
if infile != outfile:
try:
im = Image.ope...