Perl 比较文件的内容

在Perl中，我们可以通过使用 File::Compare 模块轻松地比较两个文件的内容。这个模块提供了一个叫做 compare 的函数，它有助于比较两个文件的内容，并将其作为参数指定给它。如果两个文件中的数据相同，该函数的输出为 0 ，如果传递的文件中的数据不同，返回值为 1 ，如果在访问指定/传递的文件时发生任何错误，返回值为 -1。

语法

use File::Compare;
$compare = compare('FILE_NAME_1', 'FILE_NAME_2');

注释

• 相同的内容。返回值 [0]
• 不同的内容。 返回值 [1]
• 访问文件时出错。返回值 [-1］

例如：

文件夹中存在的文件。

当文件的内容相同时

#!/usr/bin/perl
print "Content-type: text/html\n\n";
 
# Module to use compare function
use File::Compare;
 
# compare function to access the passed files.
compare = compare("gfg_a.txt", "gfg_c.txt");
 
# checking if the files are same
if (compare == 0)
{
    print "Files are equal. \n";
}
 
# checking if the files are different
elsif (compare == 1)
{
    print "Files are not equal. \n";
}
 
# checking if the file is not accessible
elsif(compare == -1)
{
    print "Error Occurred. \n";
}
 
exit;

输出

当文件的内容不同时

#!/usr/bin/perl
print "Content-type: text/html\n\n";
 
# Module to use compare function
use File::Compare;
 
# compare function to access the passed files.
compare = compare("gfg_a.txt", "gfg_b.txt");
 
# checking if the files are same
if (compare == 0)
{
    print "Files are equal. \n";
}
 
# checking if the files are different
elsif (compare == 1)
{
    print "Files are not equal. \n";
}
 
# checking if the file is not accessible
elsif(compare == -1)
{
    print "Error Occurred. \n";
}
 
exit;

输出

当文件无法访问时

#!/usr/bin/perl
print "Content-type: text/html\n\n";
 
# Module to use compare function
use File::Compare;
 
# compare function to access the passed files.
compare = compare("gfg_a.txt", "gfg_d.txt");
 
# checking if the files are same
if (compare == 0)
{
    print "Files are equal. \n";
}
 
# checking if the files are different
elsif (compare == 1)
{
    print "Files are not equal. \n";
}
 
# checking if the file is not accessible
elsif(compare == -1)
{
    print "Error occurred. The file is not accessible. \n";
}
 
exit;

输出