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Performance difference for control structures 'for' and 'foreach' in C#
...t will depend on whether you're doing any real work in the loop. In almost all cases, the difference to performance won't be significant, but the difference to readability favours the foreach loop.
I'd personally use LINQ to avoid the "if" too:
foreach (var item in list.Where(condition))
{
}
EDI...
What is the 'new' keyword in JavaScript?
...inherited properties and methods for the objects you make.
Here is an example:
ObjMaker = function() {this.a = 'first';};
// ObjMaker is just a function, there's nothing special about it that makes
// it a constructor.
ObjMaker.prototype.b = 'second';
// like all functions, ObjMaker has an acc...
How to pass a function as a parameter in Java? [duplicate]
...ce with only a single abstract method (sometimes called a SAM type), for example:
public interface MyInterface {
String doSomething(int param1, String param2);
}
then anywhere where MyInterface is used, you can substitute a lambda expression:
class MyClass {
public MyInterface myInterfac...
javascript: recursive anonymous function?
...mentations of Javascript. (note — that's a fairly old comment; some/many/all of the problems described in Kangax's blog post may be fixed in more modern browsers.)
When you give a name like that, the name is not visible outside the function (well, it's not supposed to be; that's one of the weirdn...
user authentication libraries for node.js?
...ooks to control what happens when authentication succeeds or fails.
For example, here is the two-step process to setup form-based (username and password) authentication:
passport.use(new LocalStrategy(
function(username, password, done) {
// Find the user from your DB (MongoDB, CouchDB, othe...
Escaping ampersand character in SQL string
... am trying to query a certain row by name in my sql database and it has an ampersand. I tried to set an escape character and then escape the ampersand, but for some reason this isn't working and I'm uncertain as to what exactly my problem is.
...
Get city name using geolocation
...d be changed to 'location', as in ...geocode({'location':latlng}). This example got me almost there, but the 'latlng' string no longer seems to be valid in newer apis. See: developers.google.com/maps/documentation/javascript/… for specifics.
– binarygiant
M...
How can one see the structure of a table in SQLite? [duplicate]
...
If you are using PHP you can get it this way:
<?php
$dbname = 'base.db';
$db = new SQLite3($dbname);
$sturturequery = $db->query("SELECT sql FROM sqlite_master WHERE name='foo'");
$table = $sturturequery->fetchArray...
Check that an email address is valid on iOS [duplicate]
...sses.
essentially it will look something like this
^((?>[a-zA-Z\d!#$%&'*+\-/=?^_`{|}~]+\x20*|"((?=[\x01-\x7f])[^"\\]|\\[\x01-\x7f])*"\x20*)*(?<angle><))?((?!\.)(?>\.?[a-zA-Z\d!#$%&'*+\-/=?^_`{|}~]+)+|"((?=[\x01-\x7f])[^"\\]|\\[\x01-\x7f])*")@(((?!-)[a-zA-Z\d\-]+(?<!-)\.)+...
How do I make a checkbox required on an ASP.NET form?
...)
{
e.IsValid = MyCheckBox.Checked;
}
ASP.Net code for the checkbox & validator...
<asp:CheckBox runat="server" ID="MyCheckBox" CssClass="AcceptedAgreement" />
<asp:CustomValidator runat="server" ID="CheckBoxRequired" EnableClientScript="true"
OnServerValidate="CheckBoxRequir...