在 Perl 哈希中添加和删除元素
使用简单的赋值运算符只需一行代码即可在 Perl 哈希中添加新键/值对。但若要从哈希中删除元素,则需要按照下面的例子中所示使用 delete 函数 −
示例
#!/usr/bin/perl
%data = ('John Paul' => 45, 'Lisa' => 30, 'Kumar' => 40);
@keys = keys %data;
$size = @keys;
print "1 - Hash size: is $size\n";
# adding an element to the hash;
$data{'Ali'} = 55;
@keys = keys %data;
$size = @keys;
print "2 - Hash size: is $size\n";
# delete the same element from the hash;
delete $data{'Ali'};
@keys = keys %data;
$size = @keys;
print "3 - Hash size: is $size\n";输出
此示例将产生以下结果 −
1 - Hash size: is 3 2 - Hash size: is 4 3 - Hash size: is 3
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