大约有 40,000 项符合查询结果（耗时：0.0533秒） [XML]
Null coalescing in powershell
...ms -ne $null
[string]::Join(', ', ($instances | ForEach-Object -Process { $_.GetType() }))
# Result:
System.String, System.Int32, System.Int32, System.String, System.Object[],
System.Boolean, System.Boolean
-eq works similarly, which is useful for counting null entries:
($null, 'a', $null -eq $n...
ActiveModel::ForbiddenAttributesError when creating new user
...ntroller < ApplicationController
def create
@user = User.new(user_params)
# ...
end
private
def user_params
params.require(:user).permit(:username, :email, :password, :salt, :encrypted_password)
end
end
...
Iterate a list as pair (current, next) in Python
...
Since the_list[1:] actually creates a copy of the whole list (excluding its first element), and zip() creates a list of tuples immediately when called, in total three copies of your list are created. If your list is very large, you ...
Unexpected Caching of AJAX results in IE8
... not as simple to solve.
The trick is to use Sys.Net.WebRequestManager.add_invokingRequest method in the event handler change the request url:
networkRequestEventArgs._webRequest._url = networkRequestEventArgs._webRequest._url + '&nocache=' + new Date().getMilliseconds();
I've blogged about...
Android: View.setID(int id) programmatically - how to avoid ID conflicts?
...same id number in the same hierarchy, then a call to findViewById([repeated_id]) would return the first view set with that one repeated id. That's what I meant.
– kaneda
Jun 19 '13 at 23:33
...
What is the single most influential book every programmer should read? [closed]
... For Computer Scientists http://ecx.images-amazon.com/images/I/51HCJ5R42KL._SL500_BO2,204,203,200_AA219_PIsitb-sticker-dp-arrow,TopRight,-24,-23_SH20_OU02_.jpg
Discrete Mathematics For Computer Scientists by J.K. Truss.
While this doesn't teach you programming, it teaches you fundamental mathemati...
Toggle button using two image on different state
...
<ToggleButton
android:id="@+id/toggle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/check" <!--check.xml-->
android:layout_margin="10dp"
android:textOn=""
android:textOff="...
Is it better to use Enumerable.Empty() as opposed to new List() to initialize an IEnumerable
...ems as an Enumerable:
public class Person
{
private IList<Role> _roles;
public Person()
{
this._roles = new List<Role>();
}
public string Name { get; set; }
public void AddRole(Role role)
{
//implementation
}
public IEnumerable<...
Python super() raises TypeError
...You have to design any methods that need to multiply-inherit (most notably __init__) to pass through arguments in a clean and sensible way, otherwise you'll get TypeErrors or worse debugging problems when someone tries to multiply-inherit using your class. Unless you've really designed to support MI...
How to select a node using XPath if sibling node has a specific value?
...rhaps because the question was for sibling.. ;-)
– hr_117
Jun 11 '13 at 12:16
4
Seems I actually ...