Skip to content

Latest commit

 

History

History
80 lines (55 loc) · 1.74 KB

6.md

File metadata and controls

80 lines (55 loc) · 1.74 KB

Perl 变量

原文: https://beginnersbook.com/2017/02/perl-variables/

perl 中有三种类型的变量:标量,标量和散列数组。让我们在示例的帮助下逐一学习它们。

标量

标量是单一数据单元。标量可以是整数,浮点数,字符串等。标量变量以$符号为前缀。让我们看看下面的 perl 脚本,其中我们有三个标量变量。

#!/usr/bin/perl

# Integer
$age = 29;

# String
$name = "Chaitanya Singh";

# Float
$height = 180.88;

print "Name: $name\n";
print "Age: $age\n";
print "Height: $height\n";

输出:

Name: Chaitanya Singh
Age: 29
Height: 180.88

数组

数组是标量的有序列表,数组变量的前缀为@符号,如下例所示:

#!/usr/bin/perl

@friends = ("Ajeet", "Leo", "Rahul", "Dhruv");

print "\$friends[0] = $friends[0]\n";
print "\$friends[1] = $friends[1]\n";
print "\$friends[2] = $friends[2]\n";
print "\$friends[3] = $friends[3]\n";

输出:

$friends[0] = Ajeet
$friends[1] = Leo
$friends[2] = Rahul
$friends[3] = Dhruv

哈希(也称为关联数组)

哈希是一组键值对。哈希变量以%符号为前缀。让我们看看下面的例子:

#!/usr/bin/perl

%age = ('Chaitanya Singh', 29, 'Ajeet', 28, 'Lisa', 25);

print "\$age{'Lisa'}: $age{'Lisa'}\n";
print "\$age{'Chaitanya Singh'}: $age{'Chaitanya Singh'}\n";
print "\$age{'Ajeet'}: $age{'Ajeet'}\n";

输出:

$age{'Lisa'}: 25
$age{'Chaitanya Singh'}: 29
$age{'Ajeet'}: 28