[英]Check the value of a text input
I have a PayPal button with a quantity text field. 我有一个带有数量文本字段的PayPal按钮。 How could I check to ensure this textfeild is > 0 so that it does not add to cart if quantity is not an integer >= 1?
我如何检查以确保此textfeild> 0,以便在数量不是大于等于1的整数时不会将其添加到购物车中?
Paypal carts are smart enough not to count negative orders. 贝宝(Paypal)购物车足够聪明,不会计算负面订单。 But you could also provide some javascript logic to your client-side that would prevent the action from taking place if the value is less than 1.
但是您还可以向客户端提供一些JavaScript逻辑,如果该值小于1,则会阻止该操作发生。
A bit of Javascript/jQuery as an example: 以Javascript / jQuery为例:
$("submit").click(function(e){
var qty = $(this).closest("form").find("[name='qty']").val();
if (qty < 1) {
e.preventDefault();
}
});
if ($_POST['field_name'] > 0) { ... }
For this I normally use: 为此,我通常使用:
if ( isset($_POST['quantity'])
&& preg_match('/^[1-9]\d*$/', $_POST['quantity'] ) {
}
the first test ensure you don't trigger an error if the quantity
isn't in the $_POST
array. 第一个测试确保如果
quantity
不在$_POST
数组中,则不会触发错误。 the second ensures that the string has only digits and the first isn't zero. 第二个确保字符串只有数字,第一个不为零。
This may help: 这可能会有所帮助:
if (empty($var)) {
echo '$var is either 0, empty, or not set at all';
}
http://php.net/manual/en/function.empty.php http://php.net/manual/en/function.empty.php
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.