基本上我用PHP创建了一个基本的在线商店，我创建了一个名为get_brands()的文件，它只是从db获取产品的品牌名称，如下所示：
<?php
function get_brands(){
$get_brands = "select * from brands";
$run_brands = mysqli_query($GLOBALS['con'],$get_brands);
while($row_brands=mysqli_fetch_array($run_brands)){
$brand_id = $row_brands['brand_id'];
$brand_title = $row_brands['brand_title'];
echo "
<option value='$brand_id'>$brand_title</option>
";
}
}
?>
现在我想在我的另一页内回应：
<div class='content-wrapper'>
<section class='content-header'>
<h1>
Add New Products
<small>onlinestore.danoup.com</small>
</h1>
<ol class='breadcrumb'>
<li class='active'>insertproducts.php</li>
</ol>
</section>
<?php
if(($dataSet->GetLevel()==1) || ($dataSet->GetLevel()==2)){ echo "
<section class='content'>
<div class='box box-default'>
<div class='box-header with-border'>
<h3 class='box-title'>Overall Info</h3>
<div class='box-tools pull-right'>
<!-- <button type='button' class='btn btn-box-tool' data-widget='collapse'><i class='fa fa-minus'></i></button>
<button type='button' class='btn btn-box-tool' data-widget='remove'><i class='fa fa-remove'></i></button> -->
</div>
</div>
<div class='box-body'>
<form action='' method='POST' enctype='multipart/form-data'>
<div class='row'>
<div class='col-md-6'>
<div class='form-group'>
<div class='form-group'>
<label>Product Title:</label>
<input type='text' name='product_title' class='form-control my-colorpicker1'>
</div>
</div>
<div class='form-group'>
<label>Product Category:</label>
<select class='form-control select2' name='product_cat' style='width: 100%;'>
".get_cats()."
?>
</select>
</div>
<div class='form-group'>
<label>Product Brand:</label>
<select class='form-control select2' name='product_brand' style='width: 100%;'>
".get_brands()."
</select>
</div>
<div class='form-group'>
<div class='form-group'>
<label>Product Image 1:</label>
<input type='file' name='product_img1' class='form-control my-colorpicker1'>
</div>
</div>
<div class='form-group'>
<div class='form-group'>
<label>Product Image 2:</label>
<input type='file' name='product_img2' class='form-control my-colorpicker1'>
</div>
</div>
<div class='form-group'>
<div class='form-group'>
<label>Product Image 3:</label>
<input type='file' name='product_img3' class='form-control my-colorpicker1'>
</div>
</div>
</div>
<div class='col-md-6'>
<div class='form-group'>
<div class='form-group'>
<label>Product Price:</label>
<input type='text' name='product_price' class='form-control my-colorpicker1'>
</div>
</div>
<div class='form-group'>
<div class='form-group'>
<label>Product Keywords:</label>
<input type='text' name='product_keywords' class='form-control my-colorpicker1'>
</div>
</div>
<input type='submit' name='insert_product' class='btn' value='Submit'>
</div>
</div>
<div class='row'>
<div class='col-md-12'>
<div class='box box-info'>
<div class='box-header'>
<h3 class='box-title'>Product Description:
<small>Add new product to your onlinestore</small>
</h3>
<div class='pull-right box-tools'>
<button type='button' class='btn btn-info btn-sm' data-widget='collapse' data-toggle='tooltip' title='Collapse'>
<i class='fa fa-minus'></i></button>
<button type='button' class='btn btn-info btn-sm' data-widget='remove' data-toggle='tooltip' title='Remove'>
<i class='fa fa-times'></i></button>
</div>
</div>
<div class='box-body pad'>
<textarea name='product_desc' placeholder='Add description to your product' style='width: 100%; height: 200px; font-size: 14px; line-height: 18px; border: 1px solid #dddddd; padding: 10px;'></textarea>
</div>
</div>
</div>
</div>
</form>
</div>
<div class='box-footer'>
Visit <a href='https://zite.pouyavagefi.com/documentation/onlinestores.php'>Online Store</a> documentation and know more about this plugin.
</div>
</div>
</section> ";
}else{
echo "
<section class='content'>
<div class='alert alert-warning'>
<strong>Access Denied!</strong> You don\'t have permission to access this page.
</div>
</section>
";
}
?>
</div>
现在唯一的问题是，它显示div之外的名称，而不是我设置的 select 标签内部...（查看下面的打印屏幕）：
我不知道为什么会发生这种情况，因为我设置了这样的代码：
<div class='form-group'>
<label>Product Brand:</label>
<select class='form-control select2' name='product_brand style='width: 100%;'>
".get_brands()."
</select>
</div>
所以，如果您对此有任何想法，请告诉我，我真的很感激！
答案 0 :(得分：1)
您需要从<option>函数返回get_brands标记，而不是直接回复它们。如果将函数值组合成这样的字符串，那么函数中的任何echo调用都将首先发生，因为在将字符串发送到浏览器之前，PHP会对该字符串进行评估。
一个基本的例子是：
echo 1 . ' ' . two();
function two() {
echo 2;
}
这实际上会显示2 1，因为在构建字符串时运行该函数，并且其echo语句首先运行。
为了使代码正常运行，我们可以将其更改为：
echo 1 . ' ' . two();
function two() {
return 2;
}
这将正确显示1 2，因为该功能不再直接调用echo。
对于您的示例，您应该在<option>中构建一串get_brands个标记，然后将其返回：
$return = '';
while($row_brands=mysqli_fetch_array($run_brands)){
$brand_id = $row_brands['brand_id'];
$brand_title = $row_brands['brand_title'];
$return .= "
<option value='$brand_id'>$brand_title</option>
";
}
return $return;