//gbk编码下 $s = '中文测试'; echo mb_strlen($s, 'utf-8'); echo strlen(iconv('gbk', 'utf-8', $s));
1.为什么值不相等
2.strlen 计算的是字符串的字节数还是字符数?
3.mb_strlen 计算的是什么?
回复内容:
//gbk编码下 $s = '中文测试'; echo mb_strlen($s, 'utf-8'); echo strlen(iconv('gbk', 'utf-8', $s));
1.为什么值不相等
2.strlen 计算的是字符串的字节数还是字符数?
3.mb_strlen 计算的是什么?
$s
里面有四个宽字符 由于你是gbk环境下的所以占8个字节 如果你把它转成utf-8编码的将会占12个字节strlen()
返回占多少个字节mb_strlen()
返回实际为多少个字符 如果是宽字符的话他会当成长度为一来计算
所以下面的代码
//gbk $s = '中文测试'; $s_u8 = iconv('gbk', 'utf-8', $s); var_dump(strlen($s), strlen($s_u8), mb_strlen($s, 'gbk'), mb_strlen($s_u8, 'utf-8'));
结果依次是8,12,4,4
貌似你第二句把编码写错了 但是写错了也能得到一样的结果。。不知道为什么
1.楼主的 mb_strlen()
用法是不是有点小问题。 mb_strlen是根据字符串的编码方式来计算字符数。
楼主是否是想用下面的代码:
<?php //gbk编码下 $s = '中文测试'; echo mb_strlen($s, 'gbk'); echo mb_strlen(iconv('gbk', 'utf-8', $s), 'utf-8');
长度都是4,所以首先确保传给mb_strlen的编码方式正确。
2. strlen()
只计算字节数
1、你打印一下,程序的第三行执行了iconv后的$s是乱码的,因为在执行iconv的时候出现了一点错误:Detected an illegal character in input,你把php文件的编码格式改成ANSI就不会出现这个错误。
2、在strlen计算时,对待一个UTF8的中文字符是3个长度
3、在mb_strlen计算时,选定内码为UTF8,则会将一个中文字符当作长度1来计算.

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