02-计算字符串的实际长度（字符串处理）

StringUtil.java

package com.lh.bean;
public class StringUtil {
	// 需要计算长度的字符串
	private String str;
	// 字符串的实际长度
	private int strLength;

	public String getStr() {
		return str;
	}

	public void setStr(String str) {
		this.str = str;
	}

	public int getStrLength() {
		// 将字符串转换为字符数组
		char[] c = str.toCharArray();
		// 用于保存每个字符的实际长度
		int factualLength = 0;
		for (int i = 0; i < c.length; i++) {
			// 获取字节数组的长度
			factualLength = String.valueOf(c[i]).getBytes().length;
			// 当程序编码为UTF-8时，汉字实际的字节长度为3
			if (factualLength == 3) {
				// 此处将字节长度改为2
				factualLength = 2;
			}
			// 将每个字符的长度累加，结果就是字符串的总长度
			strLength += factualLength;
		}
		return strLength;
	}

	public void setStrLength(int strLength) {
		this.strLength = strLength;
	}

}

index.jsp

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<html>
<head>
<title>My JSP 'index.jsp' starting page</title>
</head>

<body>
	<form action="getlength.jsp" method="post">
		<table>
			<tr height="35">
				<td align="center">请输入字符串：</td>
				<td><input type="text" name="str" />
				</td>
				<td align="center"><input type="submit" value="提交" />
				</td>
			</tr>
		</table>
	</form>
</body>
</html>

getlength.jsp

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<html>
<head>
<title>My JSP 'getlength.jsp' starting page</title>
</head>

<body>
	<%
		request.setCharacterEncoding("UTF-8");
		String str = request.getParameter("str");
	%>
	<jsp:useBean id="strBean" class="com.lh.bean.StringUtil"></jsp:useBean>
	<jsp:setProperty property="str" name="strBean" value="<%=str %>" />
	<table>
		<tr>
			<td>字符串：</td>
			<td align="left"><jsp:getProperty property="str" name="strBean" /></td>
		</tr>
		<tr>
			<td>实际长度：</td>
			<td><jsp:getProperty property="strLength" name="strBean" /></td>
		</tr>
	</table>
</body>
</html>