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Is there a standard function to check for null, undefined, or blank variables in JavaScript?
...n the specification at the ToBoolean section.
Furthermore, if you do not know whether a variable exists (that means, if it was declared) you should check with the typeof operator. For instance
if( typeof foo !== 'undefined' ) {
// foo could get resolved and it's defined
}
If you can be sure ...
Where are the Properties.Settings.Default stored?
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@Joel Coehoorn: True, however now in the administrator account in Windows Vista and on, you cannot get write access to Program Files without a UAC elevation prompt by default. That's the policy that changed. :)
– jasonh
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Showing the same file in both columns of a Sublime Text window
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@MattDMo , I see what you meant now. How do I remove the down vote?
– LED Fantom
Oct 22 '16 at 2:28
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Convert System.Drawing.Color to RGB and Hex Value
...g it may have some problem and need your kind advice. In addition, I dont know whether there is any existing method to do the same.
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variable === undefined vs. typeof variable === “undefined”
...d trigger the error "foo is not defined".
For local variables (which you know are declared somewhere), no such error would occur, hence the identity check.
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Redirecting Output from within Batch file
....txt
exit /b
:sub
command1
command2
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commandN
Edit 2020-04-17
Every now and then you may want to repeatedly write to two or more files. You might also want different messages on the screen. It is still possible to to do this efficiently by redirecting to undefined handles outside a parenthesi...
How can I view a git log of just one user's commits?
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I don't think it's quite as black and white as this. Now, I agree with unstun that we ought to educate people how to do things for themselves - that's a good idea. Where unstun went slightly wrong is making the assumptions a) That the OP knows how to search a man page, and more...
How to submit a form with JavaScript by clicking a link?
..."document.getElementById('form-id').submit();">submit</button>
Now, we come to the point at which you have to decide for the UI element which triggers the submit() call.
A button
<button>submit</button>
A link
<a href="#">submit</a>
Apply the aforementione...
How to find where a method is defined at runtime?
..., after a series of commits had occurred, a backend process failed to run. Now, we were good little boys and girls and ran rake test after every check-in but, due to some oddities in Rails' library loading, it only occurred when we ran it directly from Mongrel in production mode.
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Azure table storage returns 400 Bad Request
... mode, and I attach an image with the details of the exception. How can I know what went wrong? I was trying to inset data in a table. Can't azure give me more details?
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