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When to use Cast() and Oftype() in Linq
...ly the elements that can safely be cast to type x.
Cast - will try to cast all the elements into type x. if some of them are not from this type you will get InvalidCastException
EDIT
for example:
object[] objs = new object[] { "12345", 12 };
objs.Cast<string>().ToArray(); //throws InvalidCas...
Transitions on the CSS display property
I'm currently designing a CSS 'mega dropdown' menu - basically a regular CSS-only dropdown menu, but one that contains different types of content.
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What are all the possible values for HTTP “Content-Type” header?
...urce).
As you can see the list is way too big for you to validate against all of them. What you can do is validate against the general format and the type attribute to make sure that is correct (the set of options is small) and just assume that what follows it is correct (and of course catch any ex...
What is LDAP used for?
...e extremely fast read/query performance for a large scale of dataset. Typically you want to store only a small piece of information for each entry. The add/delete/update performance is relatively slower compared with read/query because the assumption is that you don’t do “update” that often.
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Difference between Observer, Pub/Sub, and Data Binding
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Here's my take on the three:
Data Binding
Essentially, at the core this just means "the value of property X on object Y is semantically bound to the value of property A on object B. No assumptions are made as to how Y knows or is fed changes on object B.
Observer, or Obser...
Python - List of unique dictionaries
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If you need all values considered and not just the ID you can use list({str(i):i for i in L}.values()) Here we use str(i) to create a unique string that represents the dictionary which is used to filter the duplicates.
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How to set child process' environment variable in Makefile
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I have GNU make 3.81, and all: <\n\t>export PROJ_ROOT=$(CURDIR)<\n\t>echo $(PROJ_ROOT)<\n> outputs the correct expansion for the first row, but only echo for the second one. PROJ_ROOT is not set after running make. Spaces around = gi...
How do you tell someone they're writing bad code? [closed]
I've been working with a small group of people on a coding project for fun. It's an organized and fairly cohesive group. The people I work with all have various skill sets related to programming, but some of them use older or outright wrong methods, such as excessive global variables, poor naming ...
Delaying AngularJS route change until model loaded to prevent flicker
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$routeProvider resolve property allows delaying of route change until data is loaded.
First define a route with resolve attribute like this.
angular.module('phonecat', ['phonecatFilters', 'phonecatServices', 'phonecatDirectives']).
config(['$routeProvid...
Compiled vs. Interpreted Languages
...et machine, but instead read and executed by some other program (which normally is written in the language of the native machine). For example, the same "+" operation would be recognised by the interpreter at run time, which would then call its own "add(a,b)" function with the appropriate arguments,...