Function strSubstring

The strSubstring() method returns the part of the string between the start and end indexes, or to the end of the string.

strSubstring() extracts characters from indexStart up to but not including indexEnd. In particular:

• If indexEnd is omitted, strSubstring() extracts characters to the end of the string.
• If indexStart is equal to indexEnd, strSubstring() returns an empty string.
• If indexStart is greater than indexEnd, then the effect of strSubstring() is as if the two arguments were swapped; see example below.

Any argument value that is less than 0 or greater than value.length is treated as if it were 0 and value.length, respectively.

Any argument value that is NaN is treated as if it were 0.

Example

const anyString = 'Nevware21';
// Displays 'N'
console.log(strSubstring(anyString, 0, 1));
console.log(strSubstring(anyString, 1, 0));

// Displays 'Nevwar'
console.log(strSubstring(anyString, 0, 6));

// Displays 'are21'
console.log(strSubstring(anyString, 4));

// Displays 'are'
console.log(strSubstring(anyString, 4, 7));

// Displays '21'
console.log(strSubstring(anyString, 7, 4));

// Displays 'Nevware'
console.log(strSubstring(anyString, 0, 7));

// Displays 'Nevware21'
console.log(strSubstring(anyString, 0, 10));
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