PHP - 如果为空值
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PHP - If null value
提问by Vince Pettit
I have the following coding:
我有以下编码：
<div class="product-top-icons">
<div class="energy-rating-1"><img src="http://www.justhome.co/skin/frontend/default/just2011/images/assets/<?php echo $_product->getAttributeText('energy_rating_one');?>.jpg"></div>
<div class="energy-rating-2"><img src="http://www.justhome.co/skin/frontend/default/just2011/images/assets/<?php echo $_product->getAttributeText('energy_rating_two');?>.jpg"></div>
<div class="energy-rating-3"><img src="http://www.justhome.co/skin/frontend/default/just2011/images/assets/<?php echo $_product->getAttributeText('energy_rating_three');?>.jpg"></div>
<div class="guarantee-icon"><img src="http://www.justhome.co/skin/frontend/default/just2011/images/assets/<?php echo $_product->getAttributeText('warranty');?>.jpg"></div>
</div>
I would like to add an if statement in there basically to say the following:
我想在那里添加一个 if 语句，基本上是说以下内容：
If the value in the 'energy_rating_one'attribute is null then don't display the division energy-rating-1, if the 'energy_rating_two'attribute is null then don't display the div energy-rating-2and so on...
如果'energy_rating_one'属性中的值为 null 则不显示除法energy-rating-1，如果'energy_rating_two'属性为 null 则不显示除法energy-rating-2等等...
采纳答案by Christophe
something like this:
像这样：
<?php if($_product->getAttributeText('energy_rating_one') !== null): ?>
<div class="energy-rating-1"><img src="http://www.justhome.co/skin/frontend/default/just2011/images/assets/<?php echo $_product->getAttributeText('energy_rating_one');?>.jpg"></div>
<?php endif; ?>
and that for all the others as well.
对所有其他人也是如此。
回答by check123
<?php
function echoIfExists($argument) {
$val = $_product->getAttributeText($argument);
if($val)
/*your echo stmt*/
}
echoIfExists('energy_rating_one');
/** continue here*/
?>
回答by Cups
Make it easy on yourself. Just change the css class rules from energy-rating-1to energy-rating-oneand echo the variable you already have i.e energy-rating-one
让自己轻松一点。只需将 css 类规则从energy-rating-1to更改energy-rating-one并回显您已经拥有的变量即可energy-rating-one
回答by jeanmatthieud
You have a function "int_to_words" to transform "int" value into a text value in this post: http://www.php.net/manual/en/function.strval.php#41988
在这篇文章中，您有一个函数“int_to_words”将“int”值转换为文本值：http://www.php.net/manual/en/function.strval.php#41988
After that, you just have to iterate into all values
之后，您只需遍历所有值
for(i = 0; i < 100; i++) {
$item = 'energy_rating_'.int_to_words($i);
if($_product->getAttributeText($item) != null){
echo "<div class=\"energy_rating_$i\"><img src=\"http://www.justhome.co/skin/frontend/default/just2011/images/assets/".$_product->getAttributeText($item).".jpg\"></div>";
}
}
回答by izip
Look at short hand if statement:
看看简写的 if 语句：
http://www.scottklarr.com/topic/76/ternary-php-short-hand-ifelse-statement/
http://www.scottklarr.com/topic/76/ternary-php-short-hand-ifelse-statement/
$total==1 ? "is 1 item" :
"are ".($total == 0 ? "no items" : "$total items"
