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How to check whether a Storage item is set?
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You can use hasOwnProperty method to check this
> localStorage.setItem('foo', 123)
undefined
> localStorage.hasOwnProperty('foo')
true
> localStorage.hasOwnProperty('bar')
false
Works in current versions of Chrome(Mac), Firefox(Mac) and Safari.
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How do you check if a selector matches something in jQuery? [duplicate]
...ggesting the most efficient way to do it seems to be:
if ($(selector).length ) {
// Do something
}
If you absolutely must have an exists() function - which will be slower- you can do:
jQuery.fn.exists = function(){return this.length>0;}
Then in your code you can use
if ($(selector).ex...
How do I step out of a loop with Ruby Pry?
...(finish command)
example:
42: def test
43: 3.times do |i|
=> 44: binding.pry
45: puts i
46: end
47: puts :finish
48: end
[1] pry(main)> f
0
1
2
Frame: 0/1 method
From: playground/sand.rb:47 main
42: def test
43: 3.times do |i|
44: ...
Default value of 'boolean' and 'Boolean' in Java
...as a default of null. Primitives have different default values:
boolean -> false
byte, char, short, int, long -> 0
float, double -> 0.0
Note (2): void has a wrapper Void which also has a default of null and is it's only possible value (without using hacks).
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Animate text change in UILabel
...while new label fading in), you don't want fade to invisible. It would result in unwanted flicker even if text is unchanged.
Use this approach instead:
CATransition *animation = [CATransition animation];
animation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseI...
Remove empty lines in text using Visual Studio
...sual Studio 2017 and above
in Current Document
use shortcut
Open Tools > Options or press Alt + T + O
Under Environment tab > Keyboard
Search for "DeleteBlank" and select Edit.DeleteBlankLines
Add a new shortcut for example Ctrl+D,Ctrl+E
Assign > OK
select all text and hit the shortcut...
Can anybody find the TFS “Unshelve” option in Visual Studio 2012?
...
Also :
File > Source Control > Find > Find Shelvesets
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What is the way to quick-switch between tabs in Xcode 4
... Tab
⌘ + SHIFT + } - Select Previous Tab
But I prefer going to XCode -> Preferences -> Key bindings and changing them to:
CTRL + TAB - Select Next Tab
CTRL + SHIFT + TAB - Select Previous Tab
...so they work the same as in Chrome or Safari.
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Replace all non-alphanumeric characters in a string
...o the rescue!
import re
s = re.sub('[^0-9a-zA-Z]+', '*', s)
Example:
>>> re.sub('[^0-9a-zA-Z]+', '*', 'h^&ell`.,|o w]{+orld')
'h*ell*o*w*orld'
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JavaScript/JQuery: $(window).resize how to fire AFTER the resize is completed?
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Here's a modification of CMS's solution that can be called in multiple places in your code:
var waitForFinalEvent = (function () {
var timers = {};
return function (callback, ms, uniqueId) {
if (!uniqueId) {
uniqueId = "Don't call this twice without a uniqueId";
}
i...