如果注册中显示的任何错误消息，所有字段（例如名字，电子邮件等）存储其价值，而不必重新填充。我无法为生日和性别选项添加相同的功能。以下是编码，请告诉我如何存储其价值
<?php
require 'config/config.php';
require 'includes/form_handlers/register_handler.php';
require 'includes/form_handlers/login_handler.php';
?>
<html>
<head>
<title>registration form</title>
</head>
<body>
<form action="register.php" method="POST">
<input type="email" name="log_email" placeholder="Email Address"
value="<?php
if(isset($_SESSION['log_email'])){
echo $_SESSION['log_email'];
}
?>" required>
<br>
<input type="password" name="log_password" placeholder="Password"
required>
<br>
<input type="submit" name="login_button" value="Login">
<br>
<?php if(in_array("Email or password was incorrect<br>", $error_array))
echo "Email or password was incorrect<br>";
?>
</form>
<form action="register.php" method="POST">
<input type="text" name="reg_fname" placeholder="First Name" value="<?php
if(isset($_SESSION['reg_fname'])){
echo $_SESSION['reg_fname'];
}
?>" required>
<br>
<?php if(in_array("Your first name must be between 2 and 30 characters<br>", $error_array))
echo "Your first name must be between 2 and 30 characters<br>"; ?>
<input type="text" name="reg_lname" placeholder="Last Name" value="<?php
if(isset($_SESSION['reg_lname'])){
echo $_SESSION['reg_lname'];
}
?>" required>
<br>
<?php if(in_array("Your last name must be between 2 and 30 characters<br>", $error_array))
echo "Your last name must be between 2 and 30 characters<br>"; ?>
<input type="email" name="reg_email" placeholder="Email" value="<?php
if(isset($_SESSION['reg_email'])){
echo $_SESSION['reg_email'];
}
?>" required>
<br>
<input type="email" name="reg_email2" placeholder="Confirm Email" value="<?php
if(isset($_SESSION['reg_email2'])){
echo $_SESSION['reg_email2'];
}
?>" required>
<br>
<?php if(in_array("Email already in use<br>", $error_array))
echo "Email already in use<br>";
else if(in_array("Invalid email format<br>", $error_array))
echo "Invalid email format<br>";
else if(in_array("Emails don't match<br>", $error_array))
echo "Emails don't match<br>"; ?>
<input type="password" name="reg_password" placeholder="Password" required>
<br>
<input type="password" name="reg_password2" placeholder="Confirm Password" required>
<br>
<?php if(in_array("Your passwords don't match<br>", $error_array))
echo "Your passwords don't match<br>";
else if(in_array("Your password should contain one uppercase letter, one lowercase letter and one special character <br>", $error_array))
echo "Your password should contain one uppercase letter, one lowercase letter and one special character <br>";
else if(in_array("Your password must be between 5 and 30 characters<br>", $error_array))
echo "Your password must be between 5 and 30 characters<br>"; ?>
Birthday
<br>
<select name='day' required>
<option disabled="disabled">Day</option>
<option selected="true" value='1'>1</option>
<option value='2'>2</option>
<option value='3'>3</option>
<option value='4'>4</option>
<option value='5'>5</option>
<option value='6'>6</option>
<option value='7'>7</option>
<option value='8'>8</option>
<option value='9'>9</option>
<option value='10'>10</option>
<option value='11'>11</option>
<option value='12'>12</option>
<option value='13'>13</option>
<option value='14'>14</option>
<option value='15'>15</option>
<option value='16'>16</option>
<option value='17'>17</option>
<option value='18'>18</option>
<option value='19'>19</option>
<option value='20'>20</option>
<option value='21'>21</option>
<option value='22'>22</option>
<option value='23'>23</option>
<option value='24'>24</option>
<option value='25'>25</option>
<option value='26'>26</option>
<option value='27'>27</option>
<option value='28'>28</option>
<option value='29'>29</option>
<option value='30'>30</option>
<option value='31'>31</option>
</select>
<select name='month' required>
<option disabled="disabled">Month</option>
<option selected="true" value='jan'>Jan</option>
<option value='feb'>Feb</option>
<option value='mar'>Mar</option>
<option value='apr'>Apr</option>
<option value='may'>May</option>
<option value='jun'>Jun</option>
<option value='jul'>Jul</option>
<option value='aug'>Aug</option>
<option value='sep'>Sep</option>
<option value='oct'>Oct</option>
<option value='nov'>Nov</option>
<option value='dec'>Dec</option>
</select>
<select name='year' required>
<option disabled="disabled">Year</option>
<option value='1990'>1990</option>
<option value='1989'>1989</option>
<option value='1988'>1988</option>
<option value='1987'>1987</option>
<option value='1986'>1986</option>
<option value='1985'>1985</option>
<option value='1984'>1984</option>
<option value='1983'>1983</option>
<option value='1982'>1982</option>
<option value='1981'>1981</option>
<option selected="true" value='1980'>1980</option>
<option value='1979'>1979</option>
<option value='1978'>1978</option>
<option value='1977'>1977</option>
<option value='1976'>1976</option>
<option value='1975'>1975</option>
<option value='1974'>1974</option>
<option value='1973'>1973</option>
<option value='1972'>1972</option>
<option value='1971'>1971</option>
<option value='1970'>1970</option>
<option value='1969'>1969</option>
<option value='1968'>1968</option>
<option value='1967'>1967</option>
<option value='1966'>1966</option>
<option value='1965'>1965</option>
<option value='1964'>1964</option>
<option value='1963'>1963</option>
<option value='1962'>1962</option>
<option value='1961'>1961</option>
<option value='1960'>1960</option>
<option value='1959'>1959</option>
<option value='1958'>1958</option>
<option value='1957'>1957</option>
<option value='1956'>1956</option>
<option value='1955'>1955</option>
<option value='1954'>1954</option>
<option value='1953'>1953</option>
<option value='1952'>1952</option>
<option value='1951'>1951</option>
<option value='1950'>1950</option>
<option value='1949'>1949</option>
<option value='1948'>1948</option>
<option value='1947'>1947</option>
<option value='1946'>1946</option>
<option value='1945'>1945</option>
<option value='1944'>1944</option>
<option value='1943'>1943</option>
<option value='1942'>1942</option>
<option value='1941'>1941</option>
<option value='1940'>1940</option>
<option value='1939'>1939</option>
<option value='1938'>1938</option>
<option value='1937'>1937</option>
<option value='1936'>1936</option>
<option value='1935'>1935</option>
<option value='1934'>1934</option>
<option value='1933'>1933</option>
<option value='1932'>1932</option>
<option value='1931'>1931</option>
<option value='1930'>1930</option>
<option value='1929'>1929</option>
<option value='1928'>1928</option>
<option value='1927'>1927</option>
<option value='1926'>1926</option>
<option value='1925'>1925</option>
<option value='1924'>1924</option>
<option value='1923'>1923</option>
<option value='1922'>1922</option>
<option value='1921'>1921</option>
<option value='1920'>1920</option>
<option value='1919'>1919</option>
<option value='1918'>1918</option>
</select>
<br>
<input type="radio" name="gender" value="male" required> Male
<input type="radio" name="gender" value="female"> Female
<input type="radio" name="gender" value="other"> Other
<br>
<input type="submit" name="register_button" value="Create Account">
<br>
<?php if(in_array("<span style='color: 14C800;'>You're all set! Go ahead and login!</span><br>", $error_array))
echo "<span style='color: 14C800;'>You're all set! Go ahead and login!</span><br>"; ?>
</form>
</body>
</html>
您可以将其与其他相同的对待，然后将其存储在会话中，然后在适当的选项标签上检查值和打印"选择"，例如此
<select name='day' required>
<option disabled="disabled">Day</option>
<php?
for($int i = 1; i <= 31; i++){
$selected = $_SESSION['day'] == $i ? "selected='true'" : '';
echo "<option value='$i' $selected>$i</option>";
}
?>
// Do the same for month and year
// It's a bit different for gender but you should get the idea
</select>