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Why can I use a function before it's defined in JavaScript?
This code always works, even in different browsers:
7 Answers
7
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Where does 'Hello world' come from?
' hello, world ' is usually the first example for any programming language. I've always wondered where this sentence came from and where was it first used.
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How to remove .htaccess password protection from a subdirectory
I have password protected my entire website using .htaccess but I would like to expose one of the sub directories so that it can be viewed without a password.
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jquery $(window).height() is returning the document height
I'm sure there is a simple error I'm making, but I am simply alerting $(window).height() and it returns the same value as $(document).height() .
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How to insert a SQLite record with a datetime set to 'now' in Android application?
...mDb.execSQL("INSERT INTO "+DATABASE_TABLE+" VALUES (null, datetime()) ");
Or the java date time capabilities :
// set the format to sql date time
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
Date date = new Date();
ContentValues initialValues = new ContentValues();
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How to change ViewPager's page?
...ut from the title of your question, I'm guessing that what you're looking for is pager.setCurrentItem( num ). That allows you to programatically switch to another page within the ViewPager.
I'd need to see a stack trace from logcat to be more specific if this is not the problem.
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How does @synchronized lock/unlock in Objective-C?
...antically there are some small technical differences, but it is basically correct to think of them as two separate interfaces implemented on top of a common (more primitive) entity.
In particular with a NSLock you have an explicit lock whereas with @synchronized you have an implicit lock associated...
How to check if a string “StartsWith” another string?
... ECMAScript 6's String.prototype.startsWith() method, but it's not yet supported in all browsers. You'll want to use a shim/polyfill to add it on browsers that don't support it. Creating an implementation that complies with all the details laid out in the spec is a little complicated. If you want a ...
What is a WeakHashMap and when to use it? [duplicate]
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Elements in a weak hashmap can be reclaimed by the garbage collector if there are no other strong references to the key object, this makes them useful for caches/lookup storage.
Weak reference are not restricted to these hash tables, you can use WeakReference for single objects. They are ...
How to do ToString for a possibly null object?
...6.0 Edit:
With C# 6.0 we can now have a succinct, cast-free version of the orignal method:
string s = myObj?.ToString() ?? "";
Or even using interpolation:
string s = $"{myObj}";
Original Answer:
string s = (myObj ?? String.Empty).ToString();
or
string s = (myObjc ?? "").ToString()
to be even mo...