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Weak and strong property setter attributes in Objective-C
What is the difference between weak and strong property setter attributes in Objective-C?
5 Answers
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Do the JSON keys have to be surrounded by quotes?
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Yes, you need quotation marks. This is to make it simpler and to avoid having to have another escape method for javascript reserved keywords, ie {for:"foo"}.
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How do I inspect the view hierarchy in iOS?
...nt. Currently I have to add asserts that test these various conditions by hand, or set different background colours on different views, and as you can imagine, that's a really tedious way to go about it.
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If a folder does not exist, create it
...ied folder. Now I want, if this folder does not exist, to first create it, and then save my file to this folder. If the folder already exists, then just save the file in it.
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How to specify test directory for mocha?
.../#mochaopts
If you want to do it by still just running mocha on the command line, but wanted to run the tests in a folder ./server-tests instead of ./test, create a file at ./test/mocha.opts with just this in the file:
server-tests
If you wanted to run everything in that folder and subdirector...
How to determine if a record is just created or updated in after_save
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It's best to differentiate with an after_update and an after_create. The callbacks can share a common method that takes an argument to indicate if it's a create or update.
– matthuhiggins
Oct 9 '13 at 23:44
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How many bytes does one Unicode character take?
...ough it sure does try.
Unicode itself is a mapping, it defines codepoints and a codepoint is a number, associated with usually a character. I say usually because there are concepts like combining characters. You may be familiar with things like accents, or umlauts. Those can be used with another ch...
The relationship could not be changed because one or more of the foreign-key properties is non-nulla
I am getting this error when I GetById() on an entity and then set the collection of child entities to my new list which comes from the MVC view.
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Android Studio: Android Manifest doesn't exists or has incorrect root tag
I got this error on Android Studio (AS):
11 Answers
11
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How can I validate a string to only allow alphanumeric characters in it?
...n use LINQ:
if (yourText.All(char.IsLetterOrDigit))
{
//just letters and digits.
}
yourText.All will stop execute and return false the first time char.IsLetterOrDigit reports false since the contract of All cannot be fulfilled then.
Note! this answer do not strictly check alphanumerics (whi...