我正在尝试在数据库中插入一个 Unicode 字符，例如：（），但是当我在 textarea 中插入那个（）时，它会在数据库中添加一个问号（？）？
数据库：_
CREATE TABLE `t1` (
`id` int(4) NOT NULL auto_increment,
`msg` varchar(500) NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8_mb4 AUTO_INCREMENT=7 ;
insert.php添加数据：
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>my page</title>
</head>
<body>
<form id="form1" name="form1" method="post" action="insert-ok.php">
<p>
<label for="textarea"></label>
<textarea name="textarea" id="textarea" cols="45" rows="5"></textarea>
</p>
<p>
<input type="submit" name="button" id="button" value="Submit" />
</p>
</form>
</body>
insert-ok.php插入和查看数据：
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>my data</title>
</head>
<body>
<?php
$con = mysql_connect("localhost","root","4530");
if (!$con)
{
die('Could not connect: ' . mysql_error());
}
mysql_query("set names 'utf8'");
mysql_select_db("test", $con);
$post= $_POST['textarea'];
$sql = "insert into t1 values('$id','$post')";
mysql_query($sql,$con);
$result=mysql_query("select * from t1 ");
while($row = mysql_fetch_array($result))
{
echo $row['msg'].'<br>';
}
?>
</body>
</html>