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How to check if a variable is null or empty string or all whitespace in JavaScript?
I need to check to see if a variable is null or has all empty spaces or is just blank ("").
12 Answers
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How can I programmatically get the MAC address of an iphone
... MAC
Somthing I stumbled across a while ago. Originally from here I modified it a bit and cleaned things up.
IPAddress.h
IPAddress.c
And to use it
InitAddresses();
GetIPAddresses();
GetHWAddresses();
int i;
NSString *deviceIP = nil;
for (i=0; i<MAXADDRS; ++i)
{
static unsigned long lo...
What is the difference between require() and library()?
What is the difference between require() and library() ?
8 Answers
8
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Why can't R's ifelse statements return vectors?
I've found R's ifelse statements to be pretty handy from time to time. For example:
9 Answers
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How to compare software version number using js? (only number)
...rom the input strings and then compare pairs of parts from the two arrays; if the parts are not equal we know which version is smaller.
There are a few of important details to keep in mind:
How should the parts in each pair be compared? The question wants to compare numerically, but what if we ha...
Why #define TRUE (1==1) in a C boolean macro instead of simply as 1?
... approach will use the actual boolean type (and resolve to true and false) if the compiler supports it. (specifically, C++)
However, it would be better to check whether C++ is in use (via the __cplusplus macro) and actually use true and false.
In a C compiler, this is equivalent to 0 and 1.
(note ...
Add a column to a table, if it does not already exist
...an use a similar construct by using the sys.columns table io sys.objects.
IF NOT EXISTS (
SELECT *
FROM sys.columns
WHERE object_id = OBJECT_ID(N'[dbo].[Person]')
AND name = 'ColumnName'
)
share
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How to split one string into multiple variables in bash shell? [duplicate]
...
If your solution doesn't have to be general, i.e. only needs to work for strings like your example, you could do:
var1=$(echo $STR | cut -f1 -d-)
var2=$(echo $STR | cut -f2 -d-)
I chose cut here because you could simply ex...
Test if a variable is a list or tuple
In python, what's the best way to test if a variable contains a list or a tuple? (ie. a collection)
13 Answers
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How to check if NSString begins with a certain character
How do you check if an NSString begins with a certain character (the character *).
10 Answers
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