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How to check for an undefined or null variable in JavaScript?
...ontext other than typeof.
if(typeof someUndeclaredVar == whatever) // works
if(someUndeclaredVar) // throws error
A variable that has been declared but not initialized is undefined.
let foo;
if (foo) //evaluates to false because foo === undefined
Undefined properties , like someExistingObj.s...
How to add items to a spinner in Android?
... answered Mar 9 '11 at 5:24
pankajagarwalpankajagarwal
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Running two projects at once in Visual Studio
...ntains two projects: one is the client, the other is the server. I would like to debug both at the same time, but I can only seem to run one of the projects during debugging.
...
CSS force image resize and keep aspect ratio
I am working with images, and I ran across a problem with aspect ratios.
23 Answers
23...
How to launch html using Chrome at “--allow-file-access-from-files” mode?
...utable... So if you move to Chrome's folder, this command will probably work too :
> .\chrome.exe --allow-file-access-from-files
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What's the difference between SortedList and SortedDictionary?
Is there any real practical difference between a SortedList<TKey,TValue> and a SortedDictionary<TKey,TValue> ? Are there any circumstances where you would specifically use one and not the other?
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MySQL “incorrect string value” error when save unicode string in Django
...character set.
MySQL has a 3 byte limit on utf-8 characters (yes, it's wack, nicely summed up by a Django developer here)
To solve this you need to:
Change your MySQL database, table and columns to use the utf8mb4 character set (only available from MySQL 5.5 onwards)
Specify the charset in your...
Difference between EXISTS and IN in SQL?
...
The exists keyword can be used in that way, but really it's intended as a way to avoid counting:
--this statement needs to check the entire table
select count(*) from [table] where ...
--this statement is true as soon as one match i...
Reading specific lines only
...line
elif i == 29:
# 30th line
elif i > 29:
break
fp.close()
Note that i == n-1 for the nth line.
In Python 2.6 or later:
with open("file") as fp:
for i, line in enumerate(fp):
if i == 25:
# 26th line
elif i == 29:
# 30th l...
Injecting Mockito mocks into a Spring bean
I would like to inject a Mockito mock object into a Spring (3+) bean for the purposes of unit testing with JUnit. My bean dependencies are currently injected by using the @Autowired annotation on private member fields.
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