javascript - 单选按钮的警报消息

Question

我正在尝试生成警告消息。当单选按钮未选中时。这是我的代码。

<form method=post name="spendform" id="spendform">
<input name="price" type="radio" class="invest-coin-check"  id="pricemethod" >
<button type=submit class="btn btn-lg btn-p-h btn-bw" id="mypayment">Make Investmen

t这是java脚本代码

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.js"></script>
<script>
    $(document).ready(function () {
        $('#mypayment').click(function () {
            if ($('#pricemethod').val() == '') {
                alert('Please Select Payment options');
                return false;
            }
        });
    });
</script>

Answer 1

使用 .is(':checked') 而不是 .val()。 .is(':checked')如果被选中则返回true，否则返回false。

$(document).ready(function() {
    $('#mypayment').click(function(){
        if(!$('#pricemethod').is(':checked')){
            alert('Please Select Payment options');
            return false;
        }
    });
});

<script src="https://code.jquery.com/jquery-1.12.4.min.js"></script>

<form method=post name="spendform" id="spendform">
    <input name="price" type="radio" class="invest-coin-check"  id="pricemethod" >
    <button type=submit class="btn btn-lg btn-p-h btn-bw" id="mypayment">Make Investmen</button>
</form>