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JavaScript isset() equivalent
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I generally use the typeof operator:
if (typeof obj.foo !== 'undefined') {
// your code here
}
It will return "undefined" either if the property doesn't exist or its value is undefined.
(See also: Difference between undefi...
String to object in JS
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Actually, the best solution is using JSON:
Documentation
JSON.parse(text[, reviver]);
Examples:
1)
var myobj = JSON.parse('{ "hello":"world" }');
alert(myobj.hello); // 'world'
2)
var myobj = JSON.parse(JSON.stringify({
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Uses for Optional
...tween wanting to use it everywhere something may be null , and nowhere at all.
14 Answers
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What exactly is Arel in Rails 3.0?
...alid SQL query, but one that doesn't make sense, or that does something totally different from what you think it does. This can never happen with ARel. (This is what the article I link to below means with "closed under composition".)
will objects/queries be "easier" to create?
Yes. For example, as...
CSS overflow-x: visible; and overflow-y: hidden; causing scrollbar issue
... edited Aug 14 '17 at 18:00
callum
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answered Jun 22 '11 at 0:13
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Finding the max/min value in an array of primitives using Java
... loop because the summaryStatistics method is a reduction operation and it allows parallelization.
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Set icon for Android application
...e Assets → select launcher icon → choose image file.
It will automatically re-size.
Done!
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count (non-blank) lines-of-code in bash
... Just habit. I read pipelines from left to right, which means I usually start with cat, then action, action, action, etc. Clearly, the end result is the same.
– Michael Cramer
Sep 24 '08 at 14:06
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Best practices for styling HTML emails [closed]
...nd do not use a <style> tag (GMail, for example, strips that tag and all it's contents).
Against your better judgement, use and abuse tables. <div>s just won't cut it (especially in Outlook).
Don't use background images, they're spotty and will annoy you.
Remember that some email client...
How to create ASP.NET Web API Url?
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The ApiController has a property called Url which is of type System.Web.Http.Routing.UrlHelper which allows you to construct urls for api controllers.
Example:
public class ValuesController : ApiController
{
// GET /api/values
public IEnumerable<...