前些天發現了一個巨牛的人工智能學習網站，通俗易懂，風趣幽默，忍不住分享一下給大家。點擊跳轉到教程。
推薦使用第二個方法，速度最快。?
方法一：用JAVA自帶的函數?
Java代碼??
- public?static?boolean?isNumeric(String?str){??
- ??for?(int?i?=?str.length();--i>=0;){????
- ???if?(!Character.isDigit(str.charAt(i))){??
- ????return?false;??
- ???}??
- ??}??
- ??return?true;??
- }??
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方法二：?
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Java代碼??
- /*?
- ??*?判斷是否為整數??
- ??*?@param?str?傳入的字符串??
- ??*?@return?是整數返回true,否則返回false??
- */??
- ??
- ??
- ??public?static?boolean?isInteger(String?str)?{????
- ????Pattern?pattern?=?Pattern.compile("^[-\\+]?[\\d]*$");????
- ????return?pattern.matcher(str).matches();????
- ??}??
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方法三：?
?
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Java代碼??
- public?static?boolean?isNumeric(String?str){??
- ????Pattern?pattern?=?Pattern.compile("[0-9]*");??
- ????return?pattern.matcher(str).matches();?????
- }??
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方法四：?
?
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Java代碼??
- public?final?static?boolean?isNumeric(String?s)?{??
- ????????if?(s?!=?null?&&?!"".equals(s.trim()))??
- ????????????return?s.matches("^[0-9]*$");??
- ????????else??
- ????????????return?false;??
- ????}??
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3方法五：用ascii碼?
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?
Java代碼??
- public?static?boolean?isNumeric(String?str){??
- ???for(int?i=str.length();--i>=0;){??
- ??????int?chr=str.charAt(i);??
- ??????if(chr<48?||?chr>57)??
- ?????????return?false;??
- ???}??
- ???return?true;??
- }???
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