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How to check if an NSDictionary or NSMutableDictionary contains a key?
...values. Even @NO, @0, and [NSNull null] evaluate as true.
Edit: Swift is now a thing.
For Swift you would try something like the following
if let value = myDictionary[myKey] {
}
This syntax will only execute the if block if myKey is in the dict and if it is then the value is stored in the va...
Rename a class in Xcode: Refactor… is grayed out (disabled). Why?
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I've been using Xcode for 5 years now, and refactoring has never worked correctly (even xcode 4.6 has major bugs where it WILL corrupt your source code!).
The workaround has always been (still works 100%, even in cases where Apple's code fails)
use shift-c...
How to update the value stored in Dictionary in C#?
... So this simple method seems also to be a better substitute for the well known ".Add" and ".TryGetValue" method without the necessity to change the value. (?) At least, if it doesn't matter to overwrite keys, for example in a situation where it is not excluded that keys are written more than once i...
MySQL - force not to use cache for testing speed of query
...rrent date/time will disable the query cache for that selection:
SELECT *,NOW() FROM TABLE
See "Prerequisites and Notes for MySQL Query Cache Use" @ http://dev.mysql.com/tech-resources/articles/mysql-query-cache.html
shar...
How to wrap text of HTML button with fixed width?
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@MGOwen it's ok now - we deadened IE6 in the meantime.
– low_rents
Nov 6 '17 at 10:44
1
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How to make a DIV visible and invisible with JavaScript
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wrong values for the labels. Those work now and no I'm not going to fiddle this, it's too simplistic.
– zellio
Feb 26 '12 at 19:27
add a com...
How to add a primary key to a MySQL table?
...g table. Otherwise it will be put at the end of the table as it is written now, which can be a little confusing when doing simple SELECT * ...
– StefanK
Apr 12 '19 at 6:45
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Hide Spinner in Input Number - Firefox 29
... this works and indeed it removes the spinners, but then you are now able to enter alphanumeric characters into it. Hope somebody finds a way to handle that scenario without having to check the entered keys if they are numbers or not.
– Jovanni G
Oct ...
SQL query to group by day
...SISTED
ALTER TABLE dbo.Sales
ADD SaleDay AS DAY(Created) PERSISTED
and now you could easily group by, order by etc. by day, month or year of the sale:
SELECT SaleDay, SUM(Amount)
FROM dbo.Sales
GROUP BY SaleDay
Those calculated fields will always be kept up to date (when your "Created" date c...
How can I set the value of a DropDownList using jQuery?
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Now, this doesn't work at all because select tag doesn't have any attribute named selectedIndex. It's a property of DOM object instead. Hence code should be: $("#mydropdownlist").get(0).selectedIndex = index_here;
...