大约有 44,000 项符合查询结果（耗时：0.0293秒） [XML]
Linq to Sql: Multiple left outer joins
...SQL:
Dim db As New ContractDataContext()
Dim query = From o In db.Orders _
Group Join v In db.Vendors _
On v.VendorNumber Equals o.VendorNumber _
Into ov = Group _
From x In ov.DefaultIfEmpty() _
Group Join s In db.Status _
On...
Convert list to dictionary using linq and not worrying about duplicates
...
LINQ solution:
// Use the first value in group
var _people = personList
.GroupBy(p => p.FirstandLastName, StringComparer.OrdinalIgnoreCase)
.ToDictionary(g => g.Key, g => g.First(), StringComparer.OrdinalIgnoreCase);
// Use the last value in group
var _peopl...
No output to console from a WPF application?
...ity]
public static class ConsoleManager
{
private const string Kernel32_DllName = "kernel32.dll";
[DllImport(Kernel32_DllName)]
private static extern bool AllocConsole();
[DllImport(Kernel32_DllName)]
private static extern bool FreeConsole();
[DllImport(Kernel32_DllName)]
...
How to make a valid Windows filename from an arbitrary string?
...em.IO.Path.GetInvalidFileNameChars())
{
fileName = fileName.Replace(c, '_');
}
Edit:
Since GetInvalidFileNameChars() will return 10 or 15 chars, it's better to use a StringBuilder instead of a simple string; the original version will take longer and consume more memory.
...
App Inventor 2 颜色代码块 · App Inventor 2 中文网
...接用它变成组件的颜色属性：
when Screen1.Initialize {
标签_标题.TextColor = colorFromHex("#FF5722")
global 主题色 = colorFromHex("#4CAF50")
}
颜色转十六进制
颜色转十六进制 是 十六进制转颜色 的反向块，把颜色转换成 #AAR...
back button callback in navigationController in iOS
...elegate if it should pop the top UINavigationItem by calling navigationBar(_:shouldPop:). UINavigationController actually implement this, but it doesn't publicly declare that it adopts UINavigationBarDelegate (why!?). To intercept this event, create a subclass of UINavigationController, declare its ...
How do I use IValidatableObject?
...
class RangeIfTrueAttribute : RangeAttribute
{
private readonly string _NameOfBoolProp;
public RangeIfTrueAttribute(string nameOfBoolProp, int min, int max) : base(min, max)
{
_NameOfBoolProp = nameOfBoolProp;
}
public RangeIfTrueAttribute(string nameOfBoolProp, double ...
Pass ruby script file to rails console
...
You can use
bundle exec rails runner "eval(File.read 'your_script.rb')"
UPDATE:
What we also have been using a lot lately is to load the rails environment from within the script itself. Consider doit.rb:
#!/usr/bin/env ruby
require "/path/to/rails_app/config/environment"
# ......
M_PI works with math.h but not with cmath in Visual Studio
... while checking through headers to see if there was anything undef'ing the _USE_MATH_DEFINES and found nothing.
So I moved the
#define _USE_MATH_DEFINES
#include <cmath>
to be the first thing in my file (I don't use PCHs so if you are you will have to have it after the #include "stdafx.h"...
How can I check if a Perl array contains a particular value?
...
Simply turn the array into a hash:
my %params = map { $_ => 1 } @badparams;
if(exists($params{$someparam})) { ... }
You can also add more (unique) params to the list:
$params{$newparam} = 1;
And later get a list of (unique) params back:
@badparams = keys %params;
...