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Differences in boolean operators: & vs && and | vs ||
...)){
}
"Short-circuiting" means the operator does not necessarily examine all conditions. In the above examples, && will examine the second condition only when a is not null (otherwise the whole statement will return false, and it would be moot to examine following conditions anyway), so th...
How to delete or add column in SQLITE?
...upports a limited subset of ALTER TABLE. The ALTER TABLE command in SQLite allows the user to rename a table or to add a new column to an existing table. It is not possible to rename a column, remove a column, or add or remove constraints from a table.
You can:
create new table as the one you ar...
When to use generic methods and when to use wild-card?
...eed such kind of relation, then you are free not to use type parameters at all.
Some other difference between using wildcards and type parameters are:
If you have only one parameterized type argument, then you can use wildcard, although type parameter will also work.
Type parameters support multi...
Why does NULL = NULL evaluate to false in SQL server
...
I disagree that null signifies "unknown". What it actually means is "no data". That might be used to represent the case where information is not known, but it is actually more likely to be used to indicate that something doesn't exist. To continue your example: What is Frank's m...
Setting Icon for wpf application (VS 08)
...ly worked for me. This is how I did it:
Put the icon in a folder <icon_path> in the project directory
Mimic the folder path <icon_path> in the solution
Add a new item (your icon) in the solution folder you created
Add the following code in the WPF window's code behind:
Icon = new Bi...
What is the definition of “interface” in object oriented programming
... one of the more overloaded and confusing terms in development.
It is actually a concept of abstraction and encapsulation. For a given "box", it declares the "inputs" and "outputs" of that box. In the world of software, that usually means the operations that can be invoked on the box (along with ar...
“The remote certificate is invalid according to the validation procedure.” using Gmail SMTP server
...onfirmation that the error is being throw because of a bad certificate.
Call this method before you call smtpclient.Send():
[Obsolete("Do not use this in Production code!!!",true)]
static void NEVER_EAT_POISON_Disable_CertificateValidation()
{
// Disabling certificate validati...
Django TemplateDoesNotExist?
... assuming that you have the apps configured in settings.py like this:
INSTALLED_APPS = (
'appname1',
'appname2',
'appname3',
)
By default Django will load the templates under templates/ directory under every installed apps. So with your directory structure, we want to move our templat...
change type of input field with jQuery
... or part of their security model, but jQuery isn't specific):
// We can't allow the type property to be changed (since it causes problems in IE)
if ( name == "type" && jQuery.nodeName( elem, "input" ) && elem.parentNode )
throw "type property can't be changed";
...
Simple Vim commands you wish you'd known earlier [closed]
I'm learning new commands in Vim all the time, but I'm sure everyone learns something new once in a while. I just recently learned about this:
...