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Detect when an image fails to load in Javascript
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You could try the following code. I can't vouch for browser compatibility though, so you'll have to test that.
function testImage(URL) {
var tester=new Image();
tester.onload=imageFound;
tester.onerror=imageNotFound;
tester.src=URL;
}
function imageFound() {
alert('That im...
Why are const parameters not allowed in C#?
It looks strange especially for C++ developers. In C++ we used to mark a parameter as const in order to be sure that its state will not be changed in the method. There are also other C++ specific reasons, like passing const ref in order to pass by ref and be sure that state will not be changed. ...
How do I pass a variable by reference?
...method, the method gets a reference to that same object and you can mutate it to your heart's delight, but if you rebind the reference in the method, the outer scope will know nothing about it, and after you're done, the outer reference will still point at the original object.
If you pass an immuta...
OAuth secrets in mobile apps
...n your data base or on the file system, but what is the best way to handle it in a mobile app (or a desktop app for that matter)?
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Prevent HTML5 video from being downloaded (right-click saved)?
... that's what browsers were designed to do: Serve content. But you can make it harder to download.
First thing's first, you could disable the contextmenu event, aka "the right click". That would prevent your regular skiddie from blatantly ripping your video by right clicking and Save As. But then th...
Initialize class fields in constructor or at declaration?
...ming in C# and Java recently and I am curious where the best place is to initialize my class fields.
15 Answers
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How do I use extern to share variables between source files?
...yword. What is an extern variable? What is the declaration like? What is its scope?
17 Answers
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How to estimate a programming task if you have no experience in it [closed]
I am having a difficult time with management asking for estimates on programming tasks that are using third-party controls that I have no prior experience with.
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Should a “static final Logger” be declared in UPPER-CASE?
... if somebody still care about this problem, please share ideas at github.com/checkstyle/checkstyle/issues/23, to distinguish where demand upper case and where not.
– Roman Ivanov
Oct 18 '13 at 23:16
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Connect Java to a MySQL database
... a fairly old way of doing things. The better way is to get a DataSource, either by looking one up that your app server container already configured for you:
Context context = new InitialContext();
DataSource dataSource = (DataSource) context.lookup("java:comp/env/jdbc/myDB");
or instantiating an...