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How do I get the first element from an IEnumerable in .net?
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If you can use LINQ you can use:
var e = enumerable.First();
This will throw an exception though if enumerable is empty: in which case you can use:
var e = enumerable.FirstOrDefault();
FirstOrDefault() will return defau...
In C# check that filename is *possibly* valid (not that it exists) [duplicate]
...tch (System.IO.PathTooLongException) { }
catch (NotSupportedException) { }
if (ReferenceEquals(fi, null)) {
// file name is not valid
} else {
// file name is valid... May check for existence by calling fi.Exists.
}
For creating a FileInfo instance the file does not need to exist.
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C# elegant way to check if a property's property is null
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could you explain what this does? What is value equal to if PropertyC is null? or if PropertyB is null? what if Object A is null?
– Kolob Canyon
May 18 '19 at 3:04
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break out of if and foreach
I have a foreach loop and an if statement. If a match is found i need to ultimately break out of the foreach.
4 Answers
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Default argument values in JavaScript functions [duplicate]
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In javascript you can call a function (even if it has parameters) without parameters.
So you can add default values like this:
function func(a, b){
if (typeof(a)==='undefined') a = 10;
if (typeof(b)==='undefined') b = 20;
//your code
}
and then you can ca...
Change Placeholder Text using jQuery
...pe=textarea], input[type=password], textarea").each(function(ev)
{
if(!$(this).val()) {
$(this).attr("placeholder", "Type your answer here");
}
});
});
Copy and paste this code in your js file, this will change all placeholder text from whole site.
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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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