在Mojolicus下一次是否可以有多条闪存消息？我有一种情况，表单可能有多个错误，我希望能够一次列出所有错误消息，而不是查找一个错误，显示一个错误、让用户修复一个错误并重复其他错误。
在这个示例中，消息在一个页面中设置，然后在另一个页面上显示，只显示最后添加的消息。
get '/' => sub {
my ($c) = @_;
$c->flash(msg => "This is message one.");
$c->flash(msg => "This is message two.");
$c->flash(msg => "This is message three.");
$c->flash(msg => "This is message four.");
$c->flash(msg => "This is message five.");
return $c->redirect_to('/second');
};
get '/second' => sub {
my ($c) = @_;
return $c->render(template => 'second');
};
app->secrets(["aren't important here"]);
app->start;
__DATA__
@@ second.html.ep
<!doctype html><html><head><title>Messages</title></head>
<body>
These are the flash messages:
<ul>
% if (my $msg = flash('msg')) {
<li><%= $msg %></li>
% }
</ul>
</body></html>
输出为
These are the flash messages:
This is message five.
我也尝试过在列表上下文中获取消息，但仍然只显示最后一条消息。
__DATA__
@@ second.html.ep
<!doctype html><html><head><title>Messages</title></head>
<body>
These are the flash messages:
<ul>
% if (my @msg = flash('msg')) {
% foreach my $m (@msg) {
<li><%= $m %></li>
% }
% }
</ul>
</body></html>
谢谢。
Flash数据存储在哈希中。每次调用flash()时，都会覆盖键'msg'的值。您可以使用flash来存储数据结构，而不是标量值：
use Mojolicious::Lite -signatures;
get '/' => sub {
my ($c) = @_;
my @messages = map ("This is message $_", qw/one two three four/);
$c->flash(msg =>@messages);
return $c->redirect_to('/second');
};
get '/second' => sub {
my ($c) = @_;
return $c->render(template => 'second');
};
app->secrets(["aren't important here"]);
app->start;
__DATA__
@@ second.html.ep
<!doctype html><html><head><title>Messages</title></head>
<body>
These are the flash messages:
<ul>
% for my $msg (@{flash('msg')//[]}) {
<li><%= $msg %></li>
% }
</ul>
</body></html>