linqjs

Posted 2020-10-28 自由的鱼

Project Description
linq.js - LINQ for javascript

Features

• implement all .NET 4.0 methods and many extra methods (inspiration from Rx, Achiral, Haskell, Ruby, etc...)
• complete lazy evaluation
• full IntelliSense support for VisualStudio
• two versions - linq.js and jquery.linq.js (jQuery plugin)
• support Windows Script Host
• binding for Reactive Extensions for JavaScript(RxJS) and IntelliSense Generator -> see documentation
• NuGet install support(linq.js, linq.js-jQuery, linq.js-Bindings)

90 Methods

Aggregate, All, Alternate, Any, Average, BufferWithCount, CascadeBreadthFirst, CascadeDepthFirst, Catch, Choice, Concat,
Contains, Count, Cycle, DefaultIfEmpty, Distinct, Do, ElementAt, ElementAtOrDefault, Empty, Except, Finally, First, FirstOrDefault, 
Flatten, ForEach, Force, From, Generate, GetEnumerator, GroupBy, GroupJoin, IndexOf, Insert, Intersect, Join, Last, LastIndexOf,
LastOrDefault, Let, Matches, Max, MaxBy, MemoizeAll, Min, MinBy, OfType, OrderBy, OrderByDescending, Pairwise, PartitionBy, 
Range, RangeDown, RangeTo, Repeat, RepeatWithFinalize, Return, Reverse, Scan, Select, SelectMany, SequenceEqual, Share, Shuffle,
Single, SingleOrDefault, Skip, SkipWhile, Sum, Take, TakeExceptLast, TakeFromLast, TakeWhile, ThenBy, ThenByDescending, ToArray,
ToDictionary, ToInfinity,ToJSON, ToLookup, ToNegativeInfinity, ToObject, ToString, Trace, Unfold, Union, Where, Write, WriteLine, Zip

• see details - linq.js Reference & LINQPad

Starting linq.js ver.3.0.0-beta!(2012/07/19)

Get the ver.3.0.4-Beta5 @2013/06/20
or NuGet Install-Package linq.js -Pre, linq.js-jQuery -Pre, linq.js-RxJS -Pre, linq.js-QUnit -Pre
Now TypeScript Generics(0.9) support!

Please try it! and give me a feedback!
http://linqjs.codeplex.com/discussions/376207

Query objects or json

• sample from http://twitter.com/statuses/public_timeline.json

var jsonArray = [
    { "user": { "id": 100, "screen_name": "d_linq" }, "text": "to objects" },
    { "user": { "id": 130, "screen_name": "c_bill" }, "text": "g" },
    { "user": { "id": 155, "screen_name": "b_mskk" }, "text": "kabushiki kaisha" },
    { "user": { "id": 301, "screen_name": "a_xbox" }, "text": "halo reach" }
]
// ["b_mskk:kabushiki kaisha", "c_bill:g", "d_linq:to objects"]
var queryResult = Enumerable.From(jsonArray)
    .Where(function (x) { return x.user.id < 200 })
    .OrderBy(function (x) { return x.user.screen_name })
    .Select(function (x) { return x.user.screen_name + ‘:‘ + x.text })
    .ToArray();
// shortcut! string lambda selector
var queryResult2 = Enumerable.From(jsonArray)
    .Where("$.user.id < 200")
    .OrderBy("$.user.screen_name")
    .Select("$.user.screen_name + ‘:‘ + $.text")
    .ToArray();

High compatibility with C# Linq

// C# LINQ (delegate)
Enumerable.Range(1, 10)
    .Where(delegate(int i) { return i % 3 == 0; })
    .Select(delegate(int i) { return i * 10; });
// linq.js - anonymous function
Enumerable.Range(1, 10)
    .Where(function(i) { return i % 3 == 0; })
    .Select(function(i) { return i * 10; });
// C# LINQ (lambda)
Enumerable.Range(1, 10).Where(i => i % 3 == 0).Select(i => i * 10);
// linq.js - lambda expression
Enumerable.Range(1, 10).Where("i => i % 3 == 0").Select("i => i * 10");
// $ is default iterator variable like Scala‘s "_" or Groovy‘s "it"
Enumerable.Range(1, 10).Where("$ % 3 == 0").Select("$ * 10");
 // "" is shorthand of "x => x" (identity function)
Enumerable.Range(4, 7).Join(Enumerable.Range(8, 5), "", "", "outer,inner=>outer*inner");

// Enumerable.From is wrap from primitive array, string(to charArray), object(to KeyValuePair[]) etc..
var array = [100, 200, 30, 40, 500, 40, 200];
var ex1 = Enumerable.From(array).Distinct().ToArray(); // [100, 200, 30, 40, 500]
var ex2 = Enumerable.From("foobar").ToArray(); // ["f", "o", "o", "b", "a", "r"];
var ex3 = Enumerable.From({foo:10, bar:20}).ToArray(); // [{Key:"foo",Value:10}, {Key:"bar",Value:20}]

// C# - AnonymousType
array.Select((val, i) => new { Value = val, Index = i });
// linq.js - object literal
Enumerable.From(array).Select("val,i=>{Value:val, Index:i}")

jQuery plugin version

// $.Enumerable
$.Enumerable.Range(1, 10).Where("$%2==0").ForEach("alert($)");

// TojQuery - Enumerable to jQuery
$.Enumerable.Range(1, 10)
    .Select(function (i) { return $("<option>").text(i)[0] })
    .TojQuery()
    .appendTo("#select1");

// toEnumerable - jQuery to Enumerable
var sum = $("#select1").children()
    .toEnumerable()
    .Select("parseInt($.text())")
    .Sum(); // 55

IntelliSense vsdoc

video - using with Visual Studio 2010

Launch in another window

video - how to debug linq.js

Launch in another window

 

with Windows Script Host

// get folder name and file name...

var dir = WScript.CreateObject("Scripting.FileSystemObject").GetFolder("C:\\");
 
// normally
var itemNames = [];
for (var e = new Enumerator(dir.SubFolders); !e.atEnd(); e.moveNext())
{
    itemNames.push(e.item().Name);
}
for (var e = new Enumerator(dir.Files); !e.atEnd(); e.moveNext())
{
    itemNames.push(e.item().Name);
}

// linq.js
var itemNames2 = Enumerable.From(dir.SubFolders).Concat(dir.Files).Select("$.Name").ToArray();
原文链接：https://archive.codeplex.com/?p=linqjs