In this article, we are going to see a few very useful string manipulation functions that we can use in Logic Apps.

Concat

• When you want to merge more than one string, you can use this concat() function.
• Example: concat('Happy','-','New','-','year')

• Output: Happy-New-year

Substring

• When you want to fetch a part of the string value using first index and length of the string, you can use substring() function. Here you need to provide 3 parameters.
  • First parameter takes the string.
  • Second parameter takes the first index
  • Third parameter takes the length.
• Example: substring('Hello World',0,4)

• Output: Hello.
  • Here, it will grab the string from index 0 till 4^th Index (Length = 4) that means total 5 characters.
  • You must be thinking if it is 4 characters length, then how it is giving 5 characters in output. The answer is it is including character at position 0 and after that 4 character so total 5.

Slice

• When you want to fetch a part of the string value using start index and last index, you can use slice() function. Here you need to provide 3 parameters

• First parameter takes the string.
• Second parameter takes the first index
• Third parameter takes the end (last) index.

• Example: slice('Good Morning',3,10)

• Output: d Morni
  • Here, it will take the string between 3^rd index and 10^th index

Replace

• When you want to replace a part of the string with another string then you can use replace() function. Here you need to provide 3 parameters. If there are multiple occurrences of the string then also it will update all the matching strings occurances
  • First parameter is an input string
  • Second parameter is the old string that we need to replace
  • Third parameter is the new string to be replace with second parameter.
• Example: replace('Good afternoon','oo','zz'). We are trying to replace double o with double z.

• Output: Gzzd Afternzzn

Guid

• This is a simple function – guid(), which doesn’t take any argument and generates a globally Unique ID.

toLower and toUpper

• toLower() – This function will turn all the characters within the function to lower case.

• toUpper() – This function will turn all the characters within the function to upper case.

indexOf

• If you want to get the index number/position of a given character or string then you can use the function indexOf(). It takes two parameters.
  • The first parameter is the main string.
  • The second parameter is the string of which we want to get the index number.
• Example: indexOf('Good Afternoon','oo')

• Output: 1

• Here there are two occurrences of ‘oo’ but still it will consider only the first occurrence.

nthIndexOf

• If you want to know the index number of a string which is repeated nth (1^st, 2^nd ,…, nth) time, then you can use the function nthIndexOf().There are three parameters in this function.
  • First parameter is the main string.
  • Second parameter is the string that we need to search
  • Third parameter is the number value which indicates the nth place of the second parameter in the first parameter.
• Example: nthIndexOf('GoodAfternoonandnoon','oo',3)

• Output: 20

• Here, we are targeting the ’oo’ string which is at the third position in the string.

lastIndexOf

• If you want to get the last index of a value in a string then you can use the function lastIndexOf(). This function takes two arguments
  • First parameter is the main string.
  • Second parameter is the string of which we need to get the last index.
• Example: lastIndexOf('GoodAfternoonandnoon','oo')
• Output: 20

startsWith and endsWith

• startsWith(): If you want to know whether the string is starting with a value or not you can use the function startsWith(). The return value of the function is Boolean (True or False).
• endsWith(): If you want to know whether the string is ending with a value or not you can use the function startsWith(). The return value of the function is Boolean (True or False).

Split

• If you want to split the string using a separator, then you can use the function split(). There are two parameters in this function.
  • First parameter is the main string.
  • Second parameter is the separator.
• Example: split('Goodnoonandafternoon','oo')

• Output: Here , as you can see the string is split into a string array.

Trim

• When you want to remove leading and trailing spaces from a given string then you can use the function trim(). There is only one parameter and that is string that you want to trim.
• Example: trim(‘ Good Morning ’)
• Output: Good Morning