LinqPlus 1.0.0

LinqPlus

Some useful LINQ extensions

Install

> dotnet add package LinqPlus --version 1.0.1

Usage

• AllNullOrWhiteSpace
• AnyNullOrWhiteSpace
• Choose
• Chunk
• CountBetween
• Cycle
• Each
• JoinedBy
• Merge
• Random
• Range
• Repeat
• Shuffle
• Slice
• ToHashSet
• ToLinkedList
• TryIndexOf
• Without
• WhereNot
• Without
• Zip

using LinqPlus;
using static LinqPlus.Linp;

AllNullOrWhiteSpace

Returns true if all input strings are empty.

string str1 = " ";
string str2 = "";
string str3 = null;
var all = AllNullOrWhiteSpace(str1,str2,str3);
// all = true

str3 = "abcd"
all = AllNullOrWhiteSpace(str1,str2,str3);
// all = false

AnyNullOrWhiteSpace

Returns true if any input string is empty.

string str1 = "a";
string str2 = "b";
string str3 = null;
var any = AnyNullOrWhiteSpace(str1,str2,str3);
// any = true

str3 = "c"
any = AllNullOrWhiteSpace(str1,str2,str3);
// any = false

Choose

Applies a function to each element of the source sequence and returns a new sequence of result elements for source elements where the function returns a couple (2-tuple) having a true as its first element and result as the second.

var strs = new[] {"a","1","b","2","c","3"};
var nums = strs.Choose(str=>(int.TryParse(str,out var v),v))
// nums = [1,2,3]

Chunk

Splits the given sequence into chunks of the given size. If the sequence length isn't evenly divisible by the chunk size, the last chunk will contain all remaining elements.

int[] nums = { 1, 2, 3, 4, 5, 6, 7 ,8 , 9 };
var chunks = nums.Chunk(4).ToArray();
// chunks = [[1, 2, 3 ,4], [5, 6, 7 ,8], [9]]

CountBetween

Returns whether the count of elements is within a given range

var arr = new int[5];

var a = arr.CountBetween(2,5);      // true
var b = arr.CountBetween(5,10);     // true
var c = arr.CountBetween(8,10);     // false
var d = arr.CountBetween(-10,-6);   // of course,it's false

Cycle

Turns a finite sequence into a circular one, or equivalently, repeats the original sequence indefinitely.

int[] arr = { 0, 1 , 3 };
var res = arr.Cycle().Take(10).ToArray();
// res = [0, 1 , 3 ,0, 1 , 3 ,0, 1 , 3 ,0]

Each

Passes every element of the sequence to the specified action and returns it afterwards.

var arr = Range(10);
// arr: [0,1,2,3,4,5,6,7,8,9]
arr.Each(Console.Write);
// output : 012345689

var arr = Range('a','f');
// arr: ['a','b','c','d','e','f']
arr.Each((v,i) => Console.WriteLine($"value={v} index={i}"));
/* output : 
    value=a index=0
    value=b index=1
    value=c index=2
    value=d index=3
    value=e index=4
    value=f index=5
*/

JoinedBy

Concatenates all items of a sequence using the specified separator between each item.

string[] strs = { "I", "love", "you" };
var word = strs.JoinedBy(" ");
// word = "I love you"

Merge

Merge multiple enumerables into one

int[][] nums =
{
    new[] { 0, 1, 2 ,3 },
    new[] { 4, 5 ,6 ,7 ,8 },
    new[] { 8, 10 },
    new[] { 11, 12 ,13 ,14 },
};

var arr = nums.Merge().ToArray();
// arr = [1, 2, 3, 4, 5, ,6 ,7 ,8 ,9 ,10 ,11 ,12 ,13 ,14]

Random

Returns a given number of random elements from a collection.

var nums = Range(20).Random(5).ToArray();
// nums = [19, 3, 5, 14, 18]

Range

Same as Python range

var ints = Range(5);
// ints = [0, 1, 2, 3, 4]
ints = Range(5, 10);
// ints = [5, 6, 7, 8, 9]
ints = Range(5, 3, 21);
// ints = [5, 8, 11, 14, 17 ,20]
var doubles = Range(4, 0.25, 6);
// doubles = [4, 4.25, 4.5, 4.75, 5, 5.25 ,5.5 ,5.75]
var str = Range('a','z');
// str = "abcdefghijklmnopqrstuvwxyz"

Repeat

Repeats a given sequence a given number of times.

int[] arr = {1 ,2 ,3};
var nums = arr.Repeat(3).ToArray(); 
// nums = [1 ,2 ,3 ,1 ,2 ,3 ,1 ,2 ,3]

Shuffle

Enumerates the specified input sequence and returns a new sequence which contains all input elements in random order.

string[] strs = { "A", "B", "C", "D" ,"E" };
string[] sf = strs.Shuffle().ToArray();

// e.g. sf = ["D", "A", "C", "E" ,"B"]

Slice

Get subarrays ,like python

var arr = Range(5, 15);
arr = [5 ,6, 7, 8, 9, 10, 11, 12, 13, 14];
var slice1 = arr.Slice(5);      // start = 5, step = 1, end = length
// slice1 = [10 ,11 ,12, 13, 14]
var slice2 = arr.Slice(1,6);    // start =1, step = 1, end = 6
// slice2 = [6, 7, 8, 9, 10]
var slice3 = arr.Slice(2,3,-1);  // start =2, step = 3 ,end = length
// slice3 = [7 ,10 ,13]
var slice4 = arr.Slice(0,2,8)   // start =0, step = 2 ,end =8
// slice4  = [5 ,7, 9, 11]

ToHashSet

Converted to HashSet

ToLinkedList

Converted to LinkedList

TryIndexOf

Try to get the value at Index.

var str = "I love you";
var persen = str.Split().TryIndexOf(2);
// persen = "you";
str = "Iloveyou";
persen = str.Split().TryIndexOf(2);
// person = null

Without

Returns the specified collection without the specified items.

var countries = { "China", "USA", "UK", "Japen" ,"Australia", "Canada"};
var englishCountries = countries.Without("China", "Japen").ToArray();
// englishCountries ={ "USA", "UK" ,"Australia" ,"Canada"}

Zip

var ids = new[] {"001", "002", "003", "004"};
var names = new[] {"Jack", "Tom", "David", "John"};
var ages = new[] {13, 19, 24, 18};
var tuples1 = (names, ages).Zip().ToArray();// or Zip(ids,names,ages)
/* tuples1 = [
    ("Jack",  13),
    ("Tom",   19),
    ("David", 24),
    ("John",  18),
]
*/
var tuples2 = (ids, names, ages).Zip().ToArray(); // or Zip(ids,names,ages)
/* tuples = [
    ("001", "Jack",  13),
    ("002", "Tom",   19),
    ("003", "David", 24),
    ("004", "John",  18),
]
*/
// Convert to anonymous object
var objs1 = (ids, names, ages).Zip((id, name, age) => new {id, name, age}).ToArray();
/* objs1 = [
    { id = "001", name = "Jack", age = 13 },
    { id = "002", name = "Tom", age = 19 },
    { id = "003", name = "David", age = 24 },
    { id = "004", name = "John", age = 18 }
]
*/
// with index
var objs2 = (ids, names, ages).Zip((_, name, age, index) => new {index, name, age}).ToArray();
/* objs1 = [
    { index = 0, name = "Jack", age = 13 },
    { index = 1, name = "Tom", age = 19 },
    { index = 2, name = "David", age = 24 },
    { index = 3, name = "John", age = 18 }
]
*/