<script>
function more(){
var MoreDetails = document.getElementById('MoreDetails');
MoreDetails.style.display ="block";
}
function same(){
var SameProduct = document.getElementById('SameProduct');
SameProduct.style.display = "block";
}
</script>
<!DOCTYPE HTML>
<?php
$con = mysqli_connect('localhost', 'root', '', 'test') or die("Cannot connect to datbase");
// $seller = $_SESSION['sellMail'];
?>
<script src="//cdn.tinymce.com/4/tinymce.min.js"></script>
<script>tinymce.init({ selector:'textarea' });</script>
<html>
<head>
</head>
<body>
<div id = "ProductForm">
<form id="product" method="POST" enctype = "multipart/form-data" novalidate>
<table align="center" width="750" border ="2">
<tr align="center">
<td colspan="7"><h2>Insert Product</h2></td>
</tr>
<tr>
<td align="right"><b>Type of Product: </b></td>
<td>
<input list="text" name="type" placeholder = "Select a type" required>
<datalist id="text">
<?php
$run = mysqli_query($con, "Select * from typeproduct");
while($row = mysqli_fetch_array($run)){
$type_title = $row['type_title'];
echo "<option>$type_title</option>";
}
?>
</datalist>
</td>
</tr>
<tr>
<td align="right"><b>Product Category: </b></td>
<td>
<select name = "prd_cat" required>
<option>Select a Category</option>
<?php
$get_cat = "Select * from categories";
$run_cat = mysqli_query($con, $get_cat);
while($row = mysqli_fetch_array($run_cat)){
$cat_id = $row['cat_id'];
$cat_name = $row['cat_name'];
echo "<option>$cat_name</option>";
}
?>
</select>
</td>
</tr>
<tr>
<td align="right"><b>Product Brand: </b></td>
<td>
<select name = "prd_brand" required>
<option>Select a Brand</option>
<?php
$get_brn = "Select * from brands";
$run_brn = mysqli_query($con, $get_brn);
while($row = mysqli_fetch_array($run_brn)){
$brn_id = $row['brand_id'];
$brn_name = $row['brand_title'];
echo "<option>$brn_name</option>";
}
?>
</select>
</td>
</tr>
<tr align="center">
<td><input type="submit" name="prdDetails" value="Insert Product"></td>
</tr>
</table>
</form>
</div>
<?php
if(isset($_POST['prdDetails'])){
$brand = $_POST['prd_brand'];
$type = $_POST['type'];
$cat = $_POST['prd_cat'];
$select = mysqli_query($con, "Select * from products where type = '$type' AND cat='$cat' AND brand = '$brand'");
if(mysqli_num_rows($select)==0){
echo "<script>more();</script>";
}else{
echo "<script>same();</script>";
$i=1;
?>
<table id="SameProduct" style="display:none">
<tr>
<td>S.No</td>
<td>Product Image</td>
<td>Product Title</td>
<td>Product Description</td>
<td>Same Product</td>
</tr>
<?php
while($row = mysqli_fetch_array($select)){
$img = $row['img'];
$title = $row['title'];
$desc = $row['p_desc'];
?>
<tr>
<td><?php echo $i;?></td>
<td><img src="Product_image/<?php echo $img;?>"</td>
<td><?php echo $title;?></td>
<td><?php echo $desc;?></td>
<td><button>Got the Same Product</button></td>
</tr>
<?php
$i++;
}
?>
<tr>
<td><button>Product Not in list</button></td>
</tr>
</table>
<?php
}
?>
<?php
}
?>
<form method="POST" id="MoreDetails" enctype="multipart/form-data">
<table style="display:none">
<tr>
<td align="right"><b>Product Image: </b></td>
<td><input type="file" name="prd_img" required/></td>
</tr>
<tr>
<td align="right"><b>Product Price: </b></td>
<td><input type="text" name="prd_price" required/></td>
</tr>
<tr>
<td align="right"><b>Product Description: </b></td>
<td><textarea name="prd_desc" cols = "20" rows="10" required></textarea></td>
</tr>
<tr>
<td align="right"><b>Product Keywords: </b></td>
<td><input type="text" name="prd_keyword" required/></td>
</tr>
<tr align="center">
<td colspan="7"><input type="submit" name="insertPrd" id="insertPrd" value="Insert Now"/></td>
</tr>
</table></form>
</body></html>
<?php
if(isset($_POST['insertPrd'])){
$title = $_POST['prd_title'];
$categ = $_POST['prd_cat'];
$brand = $_POST['prd_brand'];
$price = $_POST['prd_price'];
$desc = $_POST['prd_desc'];
$keywords = $_POST['prd_keyword'];
$img = $_FILES['prd_img']['name'];
$img_temp = $_FILES['prd_img']['tmp_name'];
move_uploaded_file($img_temp, "Product_image/$img");
$insert_prd = "INSERT INTO products(cat, brand, title, price, p_desc, img, keyword, seller) VALUES ('$categ', '$brand', '$title', '$price', '$desc', '$img', '$keywords', '$seller')";
$insert = mysqli_query($con, $insert_prd) or die("Cannot Insert");
if($insert){
echo "<script>alert('Product has been added');</script>";
echo "<script>window.open('Seller.php','_self')</script>";
}else{
echo "<script>alert('Sorry! The Product cannot be added');</script>";
echo "<script>window.open('Seller.php','_self')</script>";
}
}
?>
每当我点击prdDetails按钮时，就会出现错误 “未捕获的TypeError：无法读取'null'的属性样式”，无论是调用more（）还是调用same（）。 我目前正在研究XAMPP服务器。 除此之外一切正常。
答案 0 :(得分：1)
您对more（）和same（）的调用发生在它们在DOM中引用的元素之前。
将more（）和same（）的调用移到元素MoreDetails和SameProduct之后的某个地方。
答案 1 :(得分：0)
这是因为document.getElementById('MoreDetails');没有收到DOM元素，变量MoreDetails是null。
您应该在ID为more()的DOM elemenet之后调用函数MoreDetails，但之前调用它，这样就无法获取此DOM元素。