Perl术语：：ReadKey with Arrow Keys

Question

我在ReadMode中使用术语：：ReadKey(‘cbreak’)来读取单个字符并根据输入执行操作。这对除箭头键以外的所有其他键都很好。当按下箭头键时，动作执行3次，我理解这是因为箭头键转换为'^[[A'，等等].

如何将箭头键转换为ReadKey可以解释的任意单个值？

我尝试了以下代码，但它不起作用：

use Term::ReadKey;

ReadMode('cbreak');

my $keystroke = '';

while ($keystroke ne 'h') {

    print "Enter key: "; 

    #Read user keystroke 
    $keystroke = ReadKey(0);

    chomp($keystroke);


    if(ord($keystroke) == 27) {
         $keystroke = ('0');
    }
}

下面是我根据建议编写的代码：

use Term::RawInput;
use strict;
use warnings;

my $keystroke = '';
my $special = ''; 

while(lc($keystroke) ne 'i' && lc($keystroke) ne 't'){

    my $promptp = "Enter key: ";

    ($keystroke,$special) = rawInput($promptp, 1);

    if ($keystroke ne '') {
        print "You hit the normal '$keystroke' key\n";
    } else {
        print "You hit the special '$special' key\n";
    }

    chomp($keystroke);

    $keystroke = lc($keystroke);
}

if($keystroke eq 'i') {
    #Do something
}

if($keystroke eq 't') {
    #Do something
}

现在，不管我按什么，我都不能退出这个循环

这是输出：

Enter key: 
Enter key:
Enter key: You hit the normal 't' key

#Proceeds to function

Answer 1

这是我的解决方案..。

use Term::ReadKey;

ReadMode('cbreak');

{
    #Temporarily turn off warnings so no messages appear for uninitialized $keystroke
    #that for some reason appears for the if statement
    no warnings;

    my $keystroke = '';

    while ($keystroke ne 'h') {

        print "\nEnter key: ";

        #Read user keystroke 
        $keystroke = ReadKey(0);

        #The first character for the arrow keys (ex. '^[[A') evaluates to 27 so I check for 
        #that
        if(ord($keystroke) == 27) {
            #Flush the rest of the characters from input buffer
            #This produces an 'Use of uninitialized value...' error
            #for the other two characters, hence 'no warnings' at the beginning.
            #This will ignore the other 2 characters and only cause a single iteration
            while( defined ReadKey(-1) ) {}
        }
    ReadMode 0;
    }
}

Answer 2

Term::RawInput没有涵盖所有内容，但对于这项任务来说，这是一个很好的开端：

use Term::RawInput;
my ($keystroke,$special) = rawInput("", 1);
if ($keystroke ne '') {
    print "You hit the normal '$keystroke' key\n";
} else {
    print "You hit the special '$special' key\n";
}

Answer 3

如果你想阅读“按键”的高级语义，而不是低级的“终端字节”，你就需要一些东西来解析和收集那些多字节的序列。

对于这类任务，我编写了任期:TermKey

use Term::TermKey;

my $tk = Term::TermKey->new( \*STDIN );

print "Press any key\n";

$tk->waitkey( my $key );

print "You pressed: " . $tk->format_key( $key, 0 );