java基础类的学习---Character类

小鱼儿 2022-06-08 01:44 129阅读 0赞

我们在使用java的时候，有时会遇到判断一个字符是不是数字、字母等情况时，就会需要用到这个类(本人目前使用到的)

Character 类用于对单个字符进行操作。

Character 类在对象中包装一个基本类型 char 的值

在某些情况下，Java编译器会自动创建一个Character对象。

例如，将一个char类型的参数传递给需要一个Character类型参数的方法时，那么编译器会自动地将char类型参数转换为Character对象。 这种特征称为装箱，反过来称为拆箱。

## Character 方法 ##

下面是Character类的方法：

<table style="border:0px; margin:4px 0px; padding:0px; border-collapse:collapse; width:729px; color:rgb(51,51,51); font-family:&quot;Helvetica Neue&quot;,Helvetica,&quot;PingFang SC&quot;,&quot;Hiragino Sans GB&quot;,&quot;Microsoft YaHei&quot;,&quot;Noto Sans CJK SC&quot;,&quot;WenQuanYi Micro Hei&quot;,Arial,sans-serif; font-size:12px"> 
 <tbody style="border:0px; margin:0px; padding:0px"> 
  <tr style="border:0px; margin:0px; padding:0px; background-color:rgb(246,244,240)"> 
   <th style="border:1px solid rgb(85,85,85); margin:0px; padding:3px; color:rgb(255,255,255); background-color:rgb(85,85,85); vertical-align:top; text-align:left"> 序号</th> 
   <th style="border:1px solid rgb(85,85,85); margin:0px; padding:3px; color:rgb(255,255,255); background-color:rgb(85,85,85); vertical-align:top; text-align:left"> 方法与描述</th> 
  </tr> 
  <tr style="border:0px; margin:0px; padding:0px"> 
   <td style="border:1px solid rgb(212,212,212); margin:0px; padding:7px 5px; font-size:13px; min-width:24px; line-height:2em; vertical-align:top"> 1</td> 
   <td style="border:1px solid rgb(212,212,212); margin:0px; padding:7px 5px; font-size:13px; line-height:2em; min-width:24px; vertical-align:top"> <a href="http://www.runoob.com/java/character-isletter.html" style="border:0px; margin:0px; padding:0px; color:rgb(100,133,76)" rel="nofollow">isLetter()</a><br> 是否是一个字母</td> 
  </tr> 
  <tr style="border:0px; margin:0px; padding:0px; background-color:rgb(246,244,240)"> 
   <td style="border:1px solid rgb(212,212,212); margin:0px; padding:7px 5px; font-size:13px; min-width:24px; line-height:2em; vertical-align:top"> 2</td> 
   <td style="border:1px solid rgb(212,212,212); margin:0px; padding:7px 5px; font-size:13px; line-height:2em; min-width:24px; vertical-align:top"> <a href="http://www.runoob.com/java/character-isdigit.html" style="border:0px; margin:0px; padding:0px; color:rgb(100,133,76)" rel="nofollow">isDigit()</a><br> 是否是一个数字字符</td> 
  </tr> 
  <tr style="border:0px; margin:0px; padding:0px"> 
   <td style="border:1px solid rgb(212,212,212); margin:0px; padding:7px 5px; font-size:13px; min-width:24px; line-height:2em; vertical-align:top"> 3</td> 
   <td style="border:1px solid rgb(212,212,212); margin:0px; padding:7px 5px; font-size:13px; line-height:2em; min-width:24px; vertical-align:top"> <a href="http://www.runoob.com/java/character-iswhitespace.html" style="border:0px; margin:0px; padding:0px; color:rgb(100,133,76)" rel="nofollow">isWhitespace()</a><br> 是否是一个空格</td> 
  </tr> 
  <tr style="border:0px; margin:0px; padding:0px; background-color:rgb(246,244,240)"> 
   <td style="border:1px solid rgb(212,212,212); margin:0px; padding:7px 5px; font-size:13px; min-width:24px; line-height:2em; vertical-align:top"> 4</td> 
   <td style="border:1px solid rgb(212,212,212); margin:0px; padding:7px 5px; font-size:13px; line-height:2em; min-width:24px; vertical-align:top"> <a href="http://www.runoob.com/java/character-isuppercase.html" style="border:0px; margin:0px; padding:0px; color:rgb(100,133,76)" rel="nofollow">isUpperCase()</a><br> 是否是大写字母</td> 
  </tr> 
  <tr style="border:0px; margin:0px; padding:0px"> 
   <td style="border:1px solid rgb(212,212,212); margin:0px; padding:7px 5px; font-size:13px; min-width:24px; line-height:2em; vertical-align:top"> 5</td> 
   <td style="border:1px solid rgb(212,212,212); margin:0px; padding:7px 5px; font-size:13px; line-height:2em; min-width:24px; vertical-align:top"> <a href="http://www.runoob.com/java/character-islowercase.html" style="border:0px; margin:0px; padding:0px; color:rgb(100,133,76)" rel="nofollow">isLowerCase()</a><br> 是否是小写字母</td> 
  </tr> 
  <tr style="border:0px; margin:0px; padding:0px; background-color:rgb(246,244,240)"> 
   <td style="border:1px solid rgb(212,212,212); margin:0px; padding:7px 5px; font-size:13px; min-width:24px; line-height:2em; vertical-align:top"> 6</td> 
   <td style="border:1px solid rgb(212,212,212); margin:0px; padding:7px 5px; font-size:13px; line-height:2em; min-width:24px; vertical-align:top"> <a href="http://www.runoob.com/java/character-touppercase.html" style="border:0px; margin:0px; padding:0px; color:rgb(100,133,76)" rel="nofollow">toUpperCase()</a><br> 指定字母的大写形式</td> 
  </tr> 
  <tr style="border:0px; margin:0px; padding:0px"> 
   <td style="border:1px solid rgb(212,212,212); margin:0px; padding:7px 5px; font-size:13px; min-width:24px; line-height:2em; vertical-align:top"> 7</td> 
   <td style="border:1px solid rgb(212,212,212); margin:0px; padding:7px 5px; font-size:13px; line-height:2em; min-width:24px; vertical-align:top"> <a href="http://www.runoob.com/java/character-tolowercase.html" style="border:0px; margin:0px; padding:0px; color:rgb(100,133,76)" rel="nofollow">toLowerCase</a>()<br> 指定字母的小写形式</td> 
  </tr> 
  <tr style="border:0px; margin:0px; padding:0px; background-color:rgb(246,244,240)"> 
   <td style="border:1px solid rgb(212,212,212); margin:0px; padding:7px 5px; font-size:13px; min-width:24px; line-height:2em; vertical-align:top"> 8</td> 
   <td style="border:1px solid rgb(212,212,212); margin:0px; padding:7px 5px; font-size:13px; line-height:2em; min-width:24px; vertical-align:top"> <a href="http://www.runoob.com/java/character-tostring.html" style="border:0px; margin:0px; padding:0px; color:rgb(100,133,76)" rel="nofollow">toString</a>()<br> 返回字符的字符串形式，字符串的长度仅为1</td> 
  </tr> 
 </tbody> 
</table>

具体方法详解：http://www.runoob.com/java/java-character.html