StringUtils in javascript [closed]

Question

I'm looking for a js library like StringUtils of commons-lang in java, which contains a lot of common methods to operating strings.

Such as:

• IsEmpty/IsBlank - checks if a String contains text
• Trim/Strip - removes leading and trailing whitespace
• Equals - compares two strings null-safe
• startsWith - check if a String starts with a prefix null-safe
• endsWith - check if a String ends with a suffix null-safe
• IndexOf/LastIndexOf/Contains - null-safe index-of checks
• IndexOfAny/LastIndexOfAny/IndexOfAnyBut/LastIndexOfAnyBut - index-of any of a set of Strings
• ContainsOnly/ContainsNone/ContainsAny - does String contains only/none/any of these characters
• Substring/Left/Right/Mid - null-safe substring extractions
• SubstringBefore/SubstringAfter/SubstringBetween - substring extraction relative to other strings
• Split/Join - splits a String into an array of substrings and vice versa
• Remove/Delete - removes part of a String
• Replace/Overlay - Searches a String and replaces one String with another
• Chomp/Chop - removes the last part of a String
• LeftPad/RightPad/Center/Repeat - pads a String
• UpperCase/LowerCase/SwapCase/Capitalize/Uncapitalize - changes the case of a String
• CountMatches - counts the number of occurrences of one String in another
• IsAlpha/IsNumeric/IsWhitespace/IsAsciiPrintable - checks the characters in a String
• DefaultString - protects against a null input String
• Reverse/ReverseDelimited - reverses a String
• Abbreviate - abbreviates a string using ellipsis

It'll be better if it contains some other methods for arrays/date, etc.

Answer 1

Here we go:

IsEmpty

str.length === 0

IsBlank

str.trim().length === 0

Trim

str.trim()

Equals

str1 === str2

startsWith

str.indexOf( str2 ) === 0

IndexOf

str.indexOf( str2 )

LastIndexOf

str.lastIndexOf( str2 )

Contains

str.indexOf( str2 ) !== -1

Substring

str.substring( start, end )

Left

str.slice( 0, len )

Mid

str.substr( i, len )

Right

str.slice( -len, str.length )

And so on... (should I continue?)

Answer 2

String utils - Underscore.string

Object/array utils - Underscore

Date utils - Moment.js