一个字符指针定位的问题,请教下各位。
<?php <br /> $handle=fopen ("many.txt","r"); <br /> //首先读取第1行,读取完毕后,指针在最后一行<br /> $buffer=fgets($handle,1024); //读取第1行内容<br /> echo $buffer ."<br>"; <br /> //接着将指针向后移动5个字节<br /> echo ftell($handle)."<br>";<br /> fseek($handle,6,seek_cup); //指针向后移动6个字节<br /> //接着读取一行<br /> $buffer=fgets($handle,1024); //接着读取第1行内容<br /> echo $buffer . "<br>"; <br /> //将指针返回到到文件开始,重新读取第1行,因为是绝对位置为0<br /> fseek($handle,0); <br /> //读取一行数据,因为指针回到文件开始,所以会读取第1行数据<br /> $buffer=fgets($handle,1024); //再读取第1行文字<br /> echo $buffer ."<br>"; //输出读取内容<br /> fclose ($handle); //关闭打开文件<br />?>
程序中第一次按行读取文件之后,文件指针应该是在第一行的末尾。如果再往后移动指针应该指针是在第二行了,为什么程序结果显示的是文件指针移动到了第一行的第7个位置,相当于从头开始移动指针的。但是函数参数明明是从当前的位置往后移动6个位置啊。
这里附上many.txt 第二行我随便打的,因为程序结果只用到了第一行。
姓名:张三 年龄15 性别:男<br />llllllllllllllllllllllllllll
------解决方案--------------------
SEEK_CUR
而且应该大写
------解决方案--------------------
是 SEEK_CUR
而不是 seek_cup
seek_cup 在屏蔽错误的情况下只能是 0
也就是 SEEK_SET 了

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