Deprecated. Don't use for new development and try to migrate existing uses.
This function takes a string and attempts a conversion to the int datatype after having first stripped away (removed) all characters that are not digits. If the string contain no digits at all, or if it would overflow an int, then a value of null is returned.
The special case of a null-string will give a return value of null.
The integer value stripped and converted from the given string.