本文转载于 http://blog.sina.com.cn/s/blog_55cbb3d10100pfjl.html
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字符串提取是个麻烦有需要耐心的工作,如果针对一个文件,可以利用正则表达式提取某些字符串,如果你有成百上千个文件,则需考虑循环或文件夹操作,下面的代码介绍了如何提取一个文件夹(含子目录)中较多文件里的某一固定字符串。
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$searchdir="c:/folder"; #指定根文件夹路径
chomp $searchdir;
$searchstr="N2O_emission"; #指定欲提取的字符串
chomp $searchstr;
opendir(DIRHANDLE,$searchdir) || die "Cann't open $searchdir !";
while($file=readdir DIRHANDLE) {
??????? if (-d "$searchdir/$file") {
??????????????? printf "$searchdir/$file is a directory!n";
??????? } else {
??????????????? open(FileHandle,"$searchdir/$file") || die "cann't open $searchdir/$file !n";
??????????????? $lines=1;
??????????????? while (defined($line=<FileHandle>)) {
??????????????????????? $back=index($line,$searchstr);
??????????????????????? if ( $back != -1 ) {
??????????????????????????????? print"$file:$lines:$line"; #打印提取到的行 ??????????????????????? } ??????????????? $lines=$lines+1; ??????????????? } ??????? } ??????? close(FileHandle); } closedir(DIRHANDLE);