如何在 PHP 更新表单的“下拉菜单”中显示选定的选项？

Question

我必须在下拉列表预览中显示一个选定的选项，但目前从数据库中提取值时它只显示一个选项，而不显示数据库中的另一个。

从数据库中提取已知值时，是否有办法显示实际的下拉列表选项 (PgAdmin)（所有代码都是 HTML、CSS 或 PHP )

基本上，我希望它将数据库中的值显示为下拉菜单中的选定选项，正如您可能在下面的代码中看到的那样，我已经尝试过，但我不太确定如何进一步推进观点。也可以随时纠正我代码中的错误。我知道这有点难以消化，但希望能尽快得到答复:)

<?php
   $conn = pg_connect("host=localhost port=5432 dbname=cafe user=postgres password=password");
   if(count($_POST)>0) {
      pg_query($conn,"UPDATE cakesweetorder set id='$_POST[id]', 
         firstname='$_POST[firstname]',
         surname='$_POST[surname]',streetno='$_POST[streetno]', 
         streetname='$_POST[streetname]', 
         state = '$_POST[state]', suburb='$_POST[suburb]', 
         postcode='$_POST[postcode]', email='$_POST[email]', 
         mobno='$_POST[mobno]',colour='$_POST[colour]', 
         toping='$_POST[toping]', 
         chocosentence='$_POST[chocosentence]', 
         quantity='$_POST[quantity]', date='$_POST[date]', 
         file='$_POST[file]',
         tea='$_POST[tea]' 
      WHERE id='$_POST[id]' ");
      $message = "Record Modified Successfully";
   }
   $result = pg_query($conn,"SELECT * FROM cakesweetorder WHERE id='" . $_GET['id'] . "'");
   $row= pg_fetch_array($result);
?>
<html>
<head>
<?php 
    include_once 'head.php';
?>

<p>
<div class='text-box'>
    <div class='wrapper-glass'>
        <div class='shape-1'></div>
        <div class='shape-2'></div>
        <div class='shape-3'></div>
        <div class='shape-4'></div>
        <div class='shape-5'></div>
        <div class='shape-6'></div>
        <div class='shape-7'></div>
        <div class='shape-8'></div>
        <div class='shape-9'></div>
        <div class='shape-10'></div>
        <div class='container-glass'>  

<title>Cafe Database</title>
</head>
<body>
<form name="frmUser" method="post" action="">
<div><?php if(isset($message)) { echo $message; } 

?>    
</div>
ID: <br>
<input type="hidden" name="id" class="txtField" value="<?php echo $row['id']; ?>">
<input readonly='readonly' name="id"  value="<?php echo $row['id']; ?>">
<br>

<legend>Name</legend>

Firstname:<div class="bar"><div class="text-bar"><input type="text" class="form-control" name="firstname" id="name" placeholder="Firstname..." value="<?php echo $row['firstname']; ?>"required/></div></div>
Surname:<div class="bar"><div class="text-bar2"><input type="text" class="form-control" name="surname" id="name" placeholder="Surname..."  value="<?php echo $row['surname']; ?>"required/></div></div>


<legend>Address For Delivery</legend>
 Street No: <div class="bar"><div class="text-bar3"><input type="number" id="text-bar" class="form-control" name="streetno" placeholder="Street No..."  value="<?php echo $row['streetno']; ?>"required/><br/></div></div>
 Street: <div class="bar"><div class="text-bar4"><input type="text" id="text-bar" class="form-control" name="streetname" placeholder="Street Name..."  value="<?php echo $row['streetname']; ?>"required/><br/></div></div>
 State:  
 
 State:  
     <div class="bar"><div class="text-bar5"><select id="state" class="form-control" name="state" value="<?php echo $row['state']; ?>" name="state"></div></div>
 <optgroup label="States">
    <option value="NSW">NSW</option>
    <option value="QLD">QLD</option>
    <option value="VIC">VIC</option>
    <option value="SA">SA</option>
    <option value="NT">NT</option>
    <option value="TAS">TAS</option>
  </select><br></div></div>
 Suburb: <div class="bar"><div class="text-bar6"><input type="text" class="form-control" name="suburb" placeholder="Suburb..."  value="<?php echo $row['suburb']; ?>" required/><br/></div></div>
 Postcode: <div class="bar"><div class="text-bar7"><input type="number" class="form-control" name="postcode" placeholder="Postcode..."   value="<?php echo $row['postcode']; ?>" required/><br/></div></div>

<legend>Personal Details</legend>
 Email:<div class="bar"><div class="text-bar8"> <input type="email" class="form-control" name="email" placeholder="Email..."  value="<?php echo $row['email']; ?>" required/><br/></div></div>
 Phone Number: <div class="bar"><div class="text-bar9"><input type="number" class="form-control" name="mobno" placeholder="Phone Number..."   value="<?php echo $row['mobno']; ?>"required/><br/></div></div>

 Colour of Cake: <div class="input-color-container">
 <div class="bar"><div class="text-bar11"><input id="input-color" name="colour" class="input-color" type="color"  value="<?php echo $row['colour']; ?>"></div></div>
</div>
<label class="input-color-label" for="input-color">
</label>
 Topings: <br><br>
 <label class="checkbox-container">
<input type="checkbox" name="toping" <?php if(isset($_POST['toping']) && $_POST['toping'] = 'Vanilla') echo "checked" ?> value="<?php echo $row['toping']; ?>"><span class="checkmark"></span><span class="checkbox-txt"> Vanilla</span><br/></br></label>
<label class="checkbox-container">
<input type="checkbox" name="toping" <?php if(isset($_POST['toping']) && $_POST['toping'] = 'Chocolate') echo "checked" ?> value="<?php echo $row['toping']; ?>"><span class="checkmark"></span><span class="checkbox-txt" >Chocolate</span><br/></br></label>
<label class="checkbox-container">
<input type="checkbox" name="toping" <?php if(isset($_POST['toping']) && $_POST['toping'] = 'Caramel') echo "checked" ?> value="<?php echo $row['toping']; ?>"><span class="checkmark"></span><span class="checkbox-txt" >Caramel</span><br/></br></label>
<label class="checkbox-container">
<input type="checkbox" name="toping" <?php if(isset($_POST['toping']) && $_POST['toping'] = "Strawberry") echo "checked" ?> value="<?php echo $row['toping']; ?>"><span class="checkmark"></span><span class="checkbox-txt" >Strawberry</span><br/></br></label>
<label class="checkbox-container">
<input type="checkbox" name="toping" <?php if(isset($_POST['toping']) && $_POST['toping'] = "M&M's") echo "checked" ?> value="<?php echo $row['toping']; ?>"><span class="checkmark"></span><span class="checkbox-txt" >M&M's</span><br/></br></label>
<label class="checkbox-container">
<input type="checkbox" name="toping" <?php if(isset($_POST['toping']) && $_POST['toping'] = "Oreo") echo "checked" ?> value="<?php echo $row['toping']; ?>"><span class="checkmark"></span><span class="checkbox-txt" >Oreo</span><br/></br></label>
<label class="checkbox-container">
<input type="checkbox" name="toping" <?php if(isset($_POST['toping']) && $_POST['toping'] = "Meringue") echo "checked" ?> value="<?php echo $row['toping']; ?>"><span class="checkmark "></span><span class="checkbox-txt" >Meringue</span><br/></label>

 Chocolate Sentences: <div class="bar"><div class="text-bar12"><input type="text" class="form-control" name="chocosentence" placeholder="Chocolate sentence..." value="<?php echo $row['chocosentence']; ?>"/><br/></div></div>
 Quantity of Cakes or Sweets: <div class="bar"><div class="text-bar13"><input type="number" class="form-control" min="1" value="1" max="10" name="quantity" placeholder="Quantity..."  value="<?php echo $row['quantity']; ?>" required/><br/></div></div>
 Complimentary Tea: <br>
    <div class="container">
        <input type="radio" name="tea" value="true" <?php if(isset($_POST['tea']) && $_POST['tea'] = 't') echo "checked" ?>value="<?php echo $row['tea']; ?>">
        <label for="tea" class="label1">
            <span>YES</span>
        </label>
        <input type="radio" name="tea" <?php if(isset($_POST['tea']) && $_POST['tea'] = 'f') echo "checked" ?>value="<?php echo $row['tea']; ?>">
        <label for="tea" class="label2">    
            <span>NO</span>
        </label>
    </div>
<br><br><br><br><br>
<legend>Miscellaneos</legend>
 Date Of Delivery: <div class="bar"><div class="text-bar14"><input type="date" class="form-control" name="date" placeholder="Date of Delivery..."  value="<?php echo $row['date']; ?>" required/><br/><br><br></div></div>
 Custom Order with Instructions: <input type="file" class="form-control" name="file" placeholder="Custom Order..." /><br/>
OR Type in Instructions:
<div class="container3">
<div class="bar"><div class="text-bar15"><textarea id="my-text" name="file" rows="5" placeholder="Type Custom Order Here.." value="<?php echo $row['file']; ?>" ></textarea>
        <p id="result"></p>
    </div></div></div>
<br>
<input type="submit" name="submit"  class='signup-btn' value="Submit" class="button">

</form>
</body>
</html>TAS</option>
      </select><br></div></div>’

我试过这样的东西，但它并没有真正起作用：（下图），这是一个非常模糊的尝试，但正如我之前所说，它不起作用我真的想不通

    `<?php
    $db = pg_connect("host=localhost port=5432 dbname=SRIS user=postgres password=password");
    $result = pg_query($db, "SELECT * FROM customer where customer_id = '$_POST[customer_id]'");
    $row = pg_fetch_assoc($result);
     
    // isset is set to submit in line 14
    if (isset($_POST['submit']))
    {
     
    if ($row[pref_gender] == 'M') { 
    echo "</br>"; 
    $statement1 = "<option value='M' selected>Male</option>
    <option value='F'>Female</option>";
    }        
     
    if ($row[pref_gender] == 'F') { 
    echo "</br>"; 
    $statement1 = "<option value='F' selected>Female</option>
    <option value='M'>Male</option>";
    }        
     
    // retrieves one row of data from the table and displays the fields in the form
    // Book id is a primary key so we can't edit it        
    echo "<p>
     
    <form name='update' action='enter_primarykey.php' method='POST' >
    <li>Customer Id</li><li><input type='text' name='customer_id_updated' value='$row[customer_id]' /></li>
     
    <li>Firstname</li><li><input type='text' name='firstname_updated' value='$row[firstname]' /></li>
    <li>Surname</li><li><input type='text' name='surname updated' value='$row[surname]' /></li> 
     
    <li>Gender</li>
    <li>
    <select name='pref_gender_updated'>
    $statement1                
    </select>
    </li>
     
    <li><input type='submit' name='new' /></li>  </form>
    </p>";
    }
     
    // isset is set to new in line 37
    // uses the primary key to save all the values back into the database when submit is clicked
    if (isset($_POST['new']))
    {
    $result1 = pg_query($db, "UPDATE customer SET firstname = '$_POST[firstname_updated]', 
    surname = '$_POST[surname_updated]', pref_gender = '$_POST[pref_gender_updated]' WHERE customer_id= '$_POST[customer_id_updated]'”);`

以下是我要更改的内容。当显示从 table 中提取的数据时，我希望它显示 'QLD' 而不是显示默认的 'NSW'，我该如何调整代码来做到这一点？

`State:  
         <div class="bar"><div class="text-bar5"><select id="state" class="form-control" name="state" value="<?php echo $row['state']; ?>" name="state"></div></div>
     <optgroup label="States">
        <option value="NSW">NSW</option>
        <option value="QLD">QLD</option>
        <option value="VIC">VIC</option>
        <option value="SA">SA</option>
        <option value="NT">NT</option>
        <option value="TAS">TAS</option>
      </select><br></div></div>`

Answer 1

看起来有点像这样：

PHP

//Do Query (In your case, we can use $row['states']

HTML

`State:  
<div class="bar">
  <div class="text-bar5">
     <select id="state" class="form-control" name="state" name="state"></div></div>
       <optgroup label="States">
       <option value="NSW" <?php if($row['states'] == 'NSW')echo 'selected'; ?> >NSW</option>
       <option value="QLD" <?php if($row['states'] == 'QLD')echo 'selected'; ?> >QLD</option>
<!-- VIC will be selected -->
       <option value="VIC" <?php if($row['states'] == 'VIC')echo 'selected'; ?> >VIC</option>
<!-- VIC will be selected -->
       <option value="SA" <?php if($row['states'] == 'SA')echo 'selected'; ?> >SA</option>
       <option value="NT" <?php if($row['states'] == 'NT')echo 'selected'; ?> >NT</option>
       <option value="TAS" <?php if($row['states'] == 'TAS')echo 'selected'; ?> >TAS</option>
     </select><br>
  </div>
</div>`

Answer 2

这似乎也有效！

PHP

    $result = pg_query($conn,"SELECT * FROM cakesweetorder WHERE id='" . $_GET['id'] . "'");
$row= pg_fetch_array($result);


    if ($row['state'] == 'NSW') { 
      echo "</br>"; 
      $statement1 = "<option value='NSW' selected>NSW</option>
          <option value='QLD'>QLD</option>
          <option value='VIC' >VIC</option>
          <option value='SA'>SA</option>
          <option value='NT'>NT</option>
          <option value='TAS'>TAS</option>";
            
    }   
      
    if ($row['state'] == 'QLD') { 
      echo "</br>"; 
      $statement1 = "<option value='QLD' selected>QLD</option>
      <option value='NSW'>NSW</option>
      <option value='VIC' >VIC</option>
      <option value='SA'>SA</option>
      <option value='NT'>NT</option>
      <option value='TAS'>TAS</option>";
  } 


  if ($row['state'] == 'VIC') { 
    echo "</br>"; 
    $statement1 = "<option value='VIC' selected>VIC</option>
    <option value='NSW' >NSW</option>
    <option value='QLD'>QLD</option>
    <option value='SA'>SA</option>
    <option value='NT'>NT</option>
    <option value='TAS'>TAS</option>";
  } 
  if ($row['state'] == 'SA') { 
    echo "</br>"; 
    $statement1 = "<option value='SA' selected>SA</option>
    <option value='NSW'>NSW</option>
    <option value='QLD'>QLD</option>
    <option value='VIC'>VIC</option>
    
    <option value='NT'>NT</option>
    <option value='TAS'>TAS</option>";
  } 
  if ($row['state'] == 'NT') { 
    echo "</br>"; 
    $statement1 = " <option value='NT' selected>NT</option>
    <option value='NSW'>NSW</option>
    <option value='QLD'>QLD</option>
    <option value='VIC'>VIC</option>
    <option value='SA'>SA</option>
    <option value='TAS'>TAS</option>";
  } 
  if ($row['state'] == 'TAS') { 
    echo "</br>"; 
    $statement1 = "<option value='TAS' selected>TAS</option>
    <option value='NSW'>NSW</option>
    <option value='QLD'>QLD</option>
    <option value='VIC'>VIC</option>
    <option value='SA'>SA</option>
    <option value='NT'>NT</option>"
    ;
  }

HTML

State:  <br>
    <select id='state' class='form-control' name='state'>
    $statement1     
    </select>
  "

Answer 3

你可以用非常简单的方式做到这一点。

<?php $row= ("Your SQL QUERY WITH CONNECTION AND EXECUTION"); ?>
    <div>
      <div>
         <select id="select_state" name="state" name="state"></div></div>
           <optgroup label="States">
           <option value="NSW" <?php if($row['states'] == 'NSW')echo 'selected'; ?> >NSW</option>
           <option value="QLD" <?php if($row['states'] == 'QLD')echo 'selected'; ?> >QLD</option>
           <option value="VIC" <?php if($row['states'] == 'VIC')echo 'selected'; ?> >VIC</option>
           <option value="SA" <?php if($row['states'] == 'SA')echo 'selected'; ?> >SA</option>
           <option value="NT" <?php if($row['states'] == 'NT')echo 'selected'; ?> >NT</option>
           <option value="TAS" <?php if($row['states'] == 'TAS')echo 'selected'; ?> >TAS</option>
         </select><br>
      </div>
    </div>

如何在 PHP 更新表单的“下拉菜单”中显示选定的选项？

How to display a selected option in `drop-down menu` in a PHP update form?

php

html

postgresql

pgadmin