我想添加自定義單選按鈕（值由用戶自定義）

Question

我有我的網頁上四個單選按鈕。三個單選按鈕的值是預定義的。

我想在它前面提供的文本框自定義第四個單選按鈕。如果他/她選擇了第四個單選按鈕並且該值作爲單選按鈕值發送，用戶必須填寫文本框。

<form method="post" action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]);?>"> 

Donation: 
<input type="radio" name="donation" <?php if (isset($donation) && $donation=="20,000") echo "checked";?> value="20,000">20,000 
<input type="radio" name="donation" <?php if (isset($donation) && $donation=="10,000") echo "checked";?> value="10,000">10,000 
<input type="radio" name="donation" <?php if (isset($donation) && $donation=="5,000") echo "checked";?> value="5,000">5,000 
<input type="radio" name="donation" <?php if (isset($donation) && $donation=="$custom") echo "checked";?> value="$custom"><input type="text" name="custom" value="<?php echo $custom;?>">Not less than Rs. 3000 
<span class="error">* <?php echo $donationErr;?></span> 
<br><br> 
<input type="submit" name="submit" value="Submit"> 


<?php 
echo "<h2>Your Input:</h2>"; 

echo "<br>"; 
echo $donation; 
?> 

Answer 1

HTML

<input type= "radio" name ="radiostemp" value="" rel=""/> 
<input type= "radio" name ="radiostemp" value="" rel=""/> 
<input type= "radio" name ="radiostemp" value="" rel=""/> 
<input type= "radio" name ="radiostemp" value="" rel="attach" /> 
<input type="text" value="" id="testtype" /> 

的JavaScript

$(document).ready(function(){ 
    $("input[type=radio]").change(function(){ 
     if($(this).attr("rel") == "attach") 
     { 
      $(this).val($("#testtype").val()); 
     } 
    }); 

    $("#testtype").change(function(){ 
     $("input[type=radio]:eq(3)").val($(this).val()); 
    }); 
});