php 正则表达式只允许字母、数字、空格、逗号、句点？
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Regex for only allowing letters, numbers, space, commas, periods?
提问by user3838246
I am clueless with regex as it is complicated for me. I am working with a program that limits input from users based on a regex. I am currently after a regex that will only let the user input:
我对正则表达式一无所知，因为它对我来说很复杂。我正在使用一个基于正则表达式限制用户输入的程序。我目前正在使用一个只会让用户输入的正则表达式：
A-Z and a-z
0-9
.
,
!
?
So basically anything in a typical paragraph or web article.
所以基本上是典型段落或网络文章中的任何内容。
The program states "Enter a regular expression which entered text must match (evaluated with preg_match, using s and i flags) for it to be valid."
程序声明“输入一个正则表达式，输入的文本必须匹配（使用 preg_match 评估，使用 s 和 i 标志）才能使其有效。”
I have tried this regex with no success and I am currently searching for others to try.
我已经尝试过这个正则表达式但没有成功，我目前正在寻找其他人来尝试。
'/^[a-zA-Z0-9,.!? ]*$/'
It should allow a simple sentence such as
它应该允许一个简单的句子，例如
"HI my name is John! I like to eat apples, oranges, and grapes. Will you eat with me?
“嗨，我叫约翰！我喜欢吃苹果、橙子和葡萄。你愿意和我一起吃吗？
回答by Jeff Wurz
^[a-zA-Z0-9,.!? ]*$
^[a-zA-Z0-9,.!? ]*$
is what the regex is, it works, see example website to test regex.
正则表达式是什么，它可以工作，请参阅示例网站来测试正则表达式。
回答by Erik Hendriks
You could also use '/^[\w .,!?]+$/'
你也可以使用 '/^[\w .,!?]+$/'
The alphanumeric \w metacharacter is equivalent to the character range [A-Za-z0-9_]
字母数字 \w 元字符等效于字符范围 [A-Za-z0-9_]
eg:
例如：
if ($_SERVER["REQUEST_METHOD"] == "POST") {
if (empty($_POST["message"])) {
$messageErr = "Message cant be empty";
} elseif (preg_match('/^[\w .,!?()]+$/', $message) === false){
$messageErr = "Only aA-zZ09.,!?_ are allowed";
} else {
$message = data($_POST["message"]);
}
}
function data($data) {
$data = trim($data);
$data = stripslashes($data);
$data = htmlspecialchars($data);
return $data;
}
# Do something with $message
回答by oliver_48
You don't even need a-z or 0-9.
"[\w,.!?]"should work.
你甚至不需要 az 或 0-9。
"[\w,.!?]"应该管用。
