What is the difference between String.slice and String.substring?

slice() works like substring() with a few different behaviors. What they have in common: If start equals stop: returns an empty string If stop is omitted: extracts characters to the end of the string If either argument is greater than the string’s length, the string’s length will be used instead. Distinctions of substring(): If start > stop, then substring will swap those 2 arguments. If either argument …

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Fastest way to remove first char in a String

The second option really isn’t the same as the others – if the string is “///foo” it will become “foo” instead of “//foo”. The first option needs a bit more work to understand than the third – I would view the Substring option as the most common and readable. (Obviously each of them as an individual statement …

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How do I check if a C++ std::string starts with a certain string, and convert a substring to an int?

Use rfind overload that takes the search position pos parameter, and pass zero for it: Who needs anything else? Pure STL! Many have misread this to mean “search backwards through the whole string looking for the prefix”. That would give the wrong result (e.g. string(“tititito”).rfind(“titi”) returns 2 so when compared against == 0 would return false) and it would be inefficient (looking through …

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How to replace a substring of a string

You need to use return value of replaceAll() method. replaceAll() does not replace the characters in the current string, it returns a new string with replacement. String objects are immutable, their values cannot be changed after they are created. You may use replace() instead of replaceAll() if you don’t need regex. outputs