我正在编写一个网页。我已完成所需的一切，但是，当您输入超过 30 的任何数量时，id = "shipping" 颜色将变为红色。它可以这样做，但对于小于 30 的任何东西也可以这样做。另外，我在将提交按钮发送到服务器/网址时遇到问题。任何帮助表示赞赏!我将附上我的代码!
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title> Widgets R' Us </title>
<style>
table,
td {
border: 1px solid black;
}
</style>
<script type="text/javascript">
//Check if non -number or a negative number
function realNumber() {
var qty1 = document.getElementById("Quantity1").value;
var qty2 = document.getElementById("Quantity2").value;
var qty3 = document.getElementById("Quantity3").value;
//isNaN is a predetermined function
if ((isNaN(qty1) || qty1 < 0) || (isNaN(qty2) || qty2 < 0) || (isNaN(qty3) || qty3 < 0)) {
alert("The quantity given is not a real number or is a negative number!");
return false; //Will not allow for data to go to server.
} else {
return true;
}
}
function total() {
var p1 = document.getElementById("Price1").value; //Value is referenced to the input tag
var p2 = document.getElementById("Price2").value;
var p3 = document.getElementById("Price3").value;
var qty1 = document.getElementById("Quantity1").value;
var qty2 = document.getElementById("Quantity2").value;
var qty3 = document.getElementById("Quantity3").value;
var over = qty1 + qty2 + qty3;
if (realNumber()) {
var totals = (p1 * qty1) + (p2 * qty2) + (p3 * qty3);
var yes = (totals).toFixed(2);
document.getElementById("ProductTotal").innerHTML = "$" + yes;
if (over > 30) {
document.getElementById("shipping").style.color = "red";
} else {
document.getElementById("shipping").style.color = "black";
}
}
}
function checkOut() {
if (total()) {
if ((document.getElementById("shipping").style.color == "red") &&
(document.getElementById("extra").checked)) {
return true;
}
}
return false;
}
</script>
</head>
<body>
<div>
<h1><b><big> Widgets R' Us </b></strong>
</h1>
<h2><b> Order/Checkout </b></h2>
<form name "widgets" onsubmit="return checkOut();" action="https://www.reddit.com/" method="get">
<div id="mainTable">
<table>
<tr>
<td>Widget Model:</td>
<td>37AX-L
<td>
</tr>
<tr>
<td>Price per Unit:</td>
<td>$12.45 <input type="hidden" id="Price1" name="Price1" value="12.45" /</td>
</tr>
<tr>
<td>State:</td>
<td>Regular</td>
</tr>
<tr>
<td>Quantity:</td>
<td> <input type="text" id="Quantity1" name="Quantity1" value="0" /</td>
</tr>
</table>
<tr>
<td> </td>
<td> </td>
</tr>
<table>
<tr>
<td>Widget Model:</td>
<td>42XR-J</td>
</tr>
<tr>
<td>Price per Unit:</td>
<td>$15.34 <input type="hidden" id="Price2" name="Price2" value="15.34" /></td>
</tr>
<tr>
<td>State:</td>
<td>Regular</td>
</tr>
<tr>
<td>Quantity:</td>
<td> <input type="text" id="Quantity2" name="Quantity2" value="0" /></td>
</tr>
</table>
<tr>
<td> </td>
<td> </td>
</tr>
<table>
<tr>
<td>Widget Model:</td>
<td>93ZZ-A</td>
</tr>
<tr>
<td>Price per Unit:</td>
<td>$28.99 <input type="hidden" id="Price3" name="Price3" value="28.99" /></td>
</tr>
<tr>
<td>State:</td>
<td>Regular</td>
</tr>
<tr>
<td>Quantity:</td>
<td> <input type="text" id="Quantity3" name="Quantity3" value="0" /></td>
</tr>
</table>
<tr>
<td> </td>
<td> </td>
</tr>
<table>
<tr>
<td>Product Total:</td>
<td>
<p id="ProductTotal"> 0 </p>
</td>
</tr>
<tr>
<td> <input type="checkbox" id="extra" name="extra"> </td>
<td>
<p id="shipping">If the quantity exceeds 30 units, there will be extra shipping!</p>
</td>
</tr>
</table>
</div>
<tr>
<td> <input type="Submit" value="Submit" /> </td>
<td> <input type="button" value="Calculate" onClick="total()" /> </td>
</tr>
</form>
</body>
</html>最佳答案
您的值 qty1、qty2、qty3 有问题。这些值作为字符串读取。因此，它不是添加这些值，而是连接字符串。替换
var qty1 = document.getElementById("Quantity1").value;
var qty2 = document.getElementById("Quantity2").value;
var qty3 = document.getElementById("Quantity3").value;
与
var qty1 = parseInt(document.getElementById("Quantity1").value);
var qty2 = parseInt(document.getElementById("Quantity2").value);
var qty3 = parseInt(document.getElementById("Quantity3").value);
它将解决您的“红色”问题。
对于提交按钮，函数total() 不返回任何内容。所以改变一些东西，比如
function total() {
var p1 = document.getElementById("Price1").value; //Value is referenced to the input tag
var p2 = document.getElementById("Price2").value;
var p3 = document.getElementById("Price3").value;
var qty1 = parseInt(document.getElementById("Quantity1").value);
var qty2 = parseInt(document.getElementById("Quantity2").value);
var qty3 = parseInt(document.getElementById("Quantity3").value);
var over = qty1 + qty2 + qty3;
if (realNumber()) {
var totals = (p1 * qty1) + (p2 * qty2) + (p3 * qty3);
var yes = (totals).toFixed(2);
document.getElementById("ProductTotal").innerHTML = "$" + yes;
if (over > 30) {
document.getElementById("shipping").style.color = "red";
return true;
} else if(over>0) {
document.getElementById("shipping").style.color = "black";
return true;
}else{
document.getElementById("shipping").style.color = "black";
return false;
}
}
}
和checkout()为
function checkOut() {
if (total()) {
if (((document.getElementById("shipping").style.color == "red") &&
(document.getElementById("extra").checked))||
(document.getElementById("shipping").style.color != "red")) {
return true;
}
}
return false;
}
关于javascript - HTML 代码中的错误，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/47027811/