在Perl中，变量名以$开头。例如，$name表示一个字符串类型的变量。Perl还支持数组和哈希表类型的变量。例如，@numbers表示一个整数数组，%hash表示一个键值对哈希表。控制流 Perl支持if-else、while、for等常见的控制流语句。例如：if ($a>$b){ print "a is greater than b\n";} else { print "a ...
for ( my $i = 1; $i <= 5; ++$i ) { unshift( @array, $i ); # add $i to front of @array print "@array\n"; # display current @array } output: 1 2 1 3 2 1 4 3 2 1 5 4 3 2 1 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 另外,perl的...
$aref = \@array; # $aref 保存着指向@array的'引用' $href = \%hash; # $href 保存着指向%hash的'引用' 当你把'引用'保存在类似 $aref 或 $href的变量中,你就可以象操作其他标量一样copy或保存它。 $xy = $aref; # $xy 现在保存了指向 @array 的'引用' $p[3] = $href; # $p[3] 现在...
#!/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 si...
print"The content of the hash variable:\n"; foreach my $name(keys %marks) { #Read the key value $mark=$marks{$name}; #Print the key and the corresponding value of the key print" $name => $mark\n"; } #Add a new value
在进行字符串处理和文本分析时，有时我们需要从字符串列表中删除特殊字符。特殊字符可能是空格、标点符号...
print "new add element:$array[0][3]\n"; #delete删除元素只是将其设置为undef,$num代表删除元素的位置。 $num = delete $array[2][2]; print "the position where deleted:$num\n"; print "\$array[2][2]=$array[2][2]\n"; #重新设置值 ...
Add this line to your application code: useGeo::IPinfo; If you'd like to install from source (not necessary for use in your application), download the source and run the following commands: perl Makefile.PL make make test make install ...
hash(1) hashcheck(1) hashmake(1) hashstat(1) head(1) head(1g) helpdate(1) helpgid(1) helpint(1) helpitem(1) helppath(1) helprange(1) helpstr(1) helptime(1) helpuid(1) helpyorn(1) hexedit(1) hg(1) hist(1) history(1) hostid(1) hostid(1g) hostname(1) hpftodit(1...
If you apply one of them to an array or a hash, it will convert the array or hash to a scalar value (the length of an array, or the population info of a hash) and then work on that scalar value. This is probably not what you meant to do. See "grep" in perlfunc and "map"...