String_Extensions

A big pile of string manipulation methods for C#, to fill in some of the gaps of the default string library.

https://www.nuget.org/packages/StringExtensionsNetStdIeb/

Comparison

CompareWildcard

Match strings to patterns using * and ? placeholders. For when Regex is too much.

NaturalComparer

A comparer for use in Linq Sort(...) that respects numerical ordering.

You can drop this anywhere an IComparer is used on strings. To sort files by name with numbers in the right place:

var list = new DirectoryInfo(@"C:\temp")
    .GetFiles()
    .OrderBy(f=>f.Name, new NaturalComparer())
    .ToList();

.OrderBy(f=>f.Name, new NaturalComparer()).ToList()

Then, given these files (as ordered by default .Net sort)

File 10, File 11, File 8, File 9

Will be sorted correctly, as would be expected:

File 8, File 9, File 10, File 11

NumbersOnlyComparer

Similar to NaturalComparer, but sorts only on number parts of strings. Strings without numbers are sorted last.

All number values are treated as positive integers, with the -, ., , characters interpreted as separators.

Given

File, Users 2020-01-01, Accounts 2020-02-03, Accounts 2020-02-03_v2

this will output

Users 2020-01-01, Accounts 2020-02-03, Accounts 2020-02-03_v2, File

EqualsIgnoreNumbers

Compare strings for equality, ignoring the actual values of decimal numbers

NaturalComparer.EqualsIgnoreNumbers("Added ID 5 to DB", "Added ID 201 to DB") == true

NaturalComparer.EqualsIgnoreNumbers("Added ID 5 to DB", "ID 201 Failed") == false

Parsing

ToByteArray

Convert hex strings to byte arrays.

Take a string like BADF00BA into a byte array. String length should be a multiple of two.

Replacement

ReplaceCaseInvariant

Replace string fragments using a case-insensitive search.

Matching is case invariant, replacement is done preserving case. For example: "OnCe UpOn A tImE".ReplaceCaseInvariant("TiMe", "Moon") == "OnCe UpOn A Moon"

ReplaceAsciiCompatible

Replace latin-like letters and numbers with their ASCII equivalents.

This will replace accented forms with ones that look similar, but it will often destroy or change meaning. Do NOT use this to present output to users. It is intended to use for stored search targets. This is not exhaustive, and does not handle characters that are not latin-like (e.g. CJK)

HÉLLO, Åbjørn!".ReplaceAsciiCompatible() == "HELLO, Abjorn!"

CamelCaseToWords

Convert camelCase or PascalCase fused-word strings into space separated words.

MyABCsDoCamelCasePhrase".CamelCaseToWords() == "My ABCs Do Camel Case Phrase"

Switch case simple

Fast case switching on strings that only makes changes that don't change the number of characters in the string.

"123 £%$: AAA aaa ǉ ǆ ß".ToUpperSimple() == "123 £%$: AAA AAA Ǉ Ǆ ß"

"123 £%$: AAA aaa Ǉ Ǆ SS".ToLowerSimple() == "123 £%$: aaa aaa ǉ ǆ ss"

Switch case of single character

Set casing of characters in the string

"hello, world".UpperCaseIndex(0) == "Hello, world"

"hello, world".UpperCaseIndex(-5) == "hello, World"

Searching

FindCluster

A very simple O(n+m) algorithm for finding clusters of characters in a string. (i.e. it will find wxyz in abc zwyx abc, but not in ab xy ab wz)

This algorithm will give some false positives where the sum of character values match.

Substrings

A range of substring before/after first/last instances of a character or string.

SubstringBefore

Return the substring up to but not including the first instance of string 's'. If 's' is not found, the entire string is returned.

"once upon a time".SubstringBefore("upon") == "once "

SubstringBeforeLast

Return the substring up to but not including the last instance of string 's'. If 's' is not found, the entire string is returned.

"once upon a time up high".SubstringBeforeLast("up") == "once upon a time "

SubstringAfter

Return the substring after to but not including the first instance of string 's'. If 's' is not found, the entire string is returned.

"it happened once upon a time".SubstringAfter("once") == " upon a time"

SubstringAfterLast

Return the substring after to but not including the last instance of string 's'. If 's' is not found, the entire string is returned.

"once upon a time".SubstringAfterLast("on") == " a time"

IndexAfter / LastIndexAfter

Return the index of the first character after a match. If match is not found, -1 is returned.

"once upon a time".IndexAfter("on") == 2 "once upon a time".LastIndexAfter("on") == 9

Filtering

NormaliseWhitespace

Replace all runs of whitespace with a single space character

var output = "This\tis\u00a0a  story about \r\n a \rperson\n\t\r\n named Not, who was    tall."
        .NormaliseWhitespace(char.IsLower);

results in This is a story about a person named Not, who was tall.

FilterCharacters

Remove a string omitting characters where the function returns true

var output = "Hello, World! How are you?"
        .FilterCharacters(char.IsLower);

results in H, W! H ?

Remove

Return a string with all instances of all given unwanted strings removed, matched case sensitive.

var output = "This is not a short story about a person named Not, who was not short but tall."
        .Remove(new[]{"not", "short", "but"})