int operator ! o const i return curLen ==0; 5 /判当前串“this是否空串 String &operator =(String &ob); /将串ob赋给当前串*this String &operator +=(String &ob); /将串ob连接到当前串“ths之后 char &operator [ int 1); /取当前串“th的第i个字符 int Find( string &e pat ) const;int operator ! ( ) const { return curLen == 0; } //判当前串*this是否空串 String &operator = (String &ob); //将串ob赋给当前串*this String &operator += (String &ob); //将串ob连接到当前串*this之后 char &operator [ ] ( int i ); //取当前串*this的第 i 个字符 int Find ( String& pat ) const; }