選擇所需的屬性

Question

如何使選擇表單爲必填項？我嘗試了「需要」，但它不起作用。

<div class="form-group"> 
    <label for="sel2">How many years have you been trading *</label> 
    <select class="form-control" id="sel2" required> 
     <option>Please select one</option> 
     <option>Start Up</option> 
     <option value="1-2">1-3</option> 
     <option value="3-4">3-4</option> 
     <option value="5more">5 or more</option> 
    </select> 
</div> 

而且爲這一個，我只是從網站得到這個，我下載的zip文件，但我需要添加所需的屬性

<div class="form-group"> 
    <label>Country *</label><br> 
    <div id="basic" data-input-name="country" required></div> 
</div> 


<script> 
$('#basic').flagStrap(); 

$('#origin').flagStrap({ 
    placeholder: { 
     value: "", 
     text: "Country of origin" 
    } 
}); 

$('#options').flagStrap({ 
    countries: { 
     "AU": "Australia", 
     "GB": "United Kingdom", 
     "US": "United States" 
    }, 
    buttonSize: "btn-sm", 
    buttonType: "btn-info", 
    labelMargin: "10px", 
    scrollable: false, 
    scrollableHeight: "350px" 
}); 

$('#advanced').flagStrap({ 
    buttonSize: "btn-lg", 
    buttonType: "btn-primary", 
    labelMargin: "20px", 
    scrollable: false, 
    scrollableHeight: "350px", 
    onSelect: function (value, element) { 
     alert(value); 
     console.log(element); 
    } 
}); 
</script> 

Answer 1

必不在這裏沃金，因爲你沒有設置貴在所有option.Set值前兩個選項：

<link href="view/css/flags.css" rel="stylesheet"> 

<select class="form-control" id="sel2" required> 
     <option value="">Please select one</option> 
     <option value="startup">Start Up</option> 
     <option value="1-2">1-3</option> 
     <option value="3-4">3-4</option> 
     <option value="5more">5 or more</option> 
</select> 

<script> 
$('#basic').flagStrap(); 

$('#origin').flagStrap({ 
    placeholder: { 
     value: "", 
     text: "Country of origin" 
    } 
}); 

$('#options').flagStrap({ 
    countries: { 
     "AU": "Australia", 
     "GB": "United Kingdom", 
     "US": "United States" 
    }, 
    buttonSize: "btn-sm", 
    buttonType: "btn-info", 
    labelMargin: "10px", 
    scrollable: false, 
    scrollableHeight: "350px" 
}); 

$('#advanced').flagStrap({ 
    buttonSize: "btn-lg", 
    buttonType: "btn-primary", 
    labelMargin: "20px", 
    scrollable: false, 
    scrollableHeight: "350px", 
    onSelect: function (value, element) { 
     alert(value); 
     console.log(element); 
    } 
}); 
</script>