<form action="" method="post">
<labal>姓名:</labal> <input style="width:105px" type="text" name="search_name" id="search_name" placeholder="姓名">
&nbsp
<labal>性别:</labal>
<input type="radio" name="search_sex" id="man" value="0">男
<input type="radio" name="search_sex" id="women" value="1">女
&nbsp
<labal>年龄:</labal><input style="width:105px" type="text" name="search_age" id="add_age"placeholder="年龄">
&nbsp
<labal>邮箱:</labal><input style="width:150px" type="text" name="search_email" id="search_email" placeholder="邮箱">
<input id="b" name="submit" style="width:60px" type="submit" value="检索">
</form>

//接收用户输入的数据$name = $sex = $age = $email = "";if (isset($_POST['submit'])) {
    if (isset($_POST['search_name'])) {
    	$name = $_POST['search_name'];
    }
    if (isset($_POST['search_sex'])) {
    	$sex = $_POST['search_sex'];
    }
    if (isset($_POST['search_age'])) {
    	$age = $_POST['search_age'];
    }
    if (isset($_POST['search_email'])) {
    	$email = $_POST['search_email'];
    }//执行检索sql$search_sql = $myTest->searchData($name,$sex,$age,$email);$result = $myTest->sqlRun($search_sql);

public function searchData($name,$sex,$age,$email){

		switch ($name) {
			//未输入姓名
			case null:
				$name_info='';
				break;
			     //根据姓名模糊查询
			    default:
				$name_info=" and name LIKE '%".$name."%'";
				break;
		}
		switch ($sex) {
			//未输入性别
			case null:
				$sex_info='';
				break;
			//根据性别准确查询
			default:
				$sex_info=' and sex='.$sex;
				break;
		}
		switch ($age) {
			//未输入年龄
			case null:
				$age_info='';
				break;
			//根据年龄准确查询
			default:
				$age_info=' and age='.$age;
				break;
		}
		switch ($email) {
			//未输入邮箱
			case null:
				$email_info='';
				break;
			//根据邮箱模糊查询
			default:
				$email_info=" and email LIKE '%".$email."%'";
				break;
		}$search_sql='SELECT * FROM users WHERE 1=1'.$name_info.$sex_info.$age_info.$email_info;'';return $search_sql;
	}