Manipulating data is an important part of any application. As JavaScript has gained more market share the need to use the language to parse and extract data has risen.JavaScript has native members of the String object to help extract sub-strings based on character position: substring, substr and slice. Each return a string, extracted from an initial string based on start position and a length.On the surface they look almost identical, but have some subtle differences.substring(indexStart[, indexEnd]): returns the part of the string between the start and end indexes, or to the end of the string.substr(start[, length]): returns the part of a string between the start index and a number of characters after it.slice(beginIndex[, endIndex]): extracts a section of a string and returns it as a new string.They also have different rules on how to deal with negative numbers and values outside the length of the source string. When you supply slice with a negative number it subtracts the number from the strings length.


Who Upvoted this Story