Converts the characters "&", "<", ">", '"', and "'" in
string to their
corresponding HTML entities.
Note: No other characters are escaped. To escape additional characters use a third-party library like he.
Though the ">" character is escaped for symmetry, characters like ">" and "/" don't need escaping in HTML and have no special meaning unless they're part of a tag or unquoted attribute value. See Mathias Bynens's article (under "semi-related fun fact") for more details.
When working with HTML you should always quote attribute values to reduce XSS vectors.
The string to escape.
Returns the escaped string.