<input type="hidden" name="grade_id[]" value="">
<div class="form-group col-sm-5">
    <div class="input-group">
        <input type="text" 
               data-errormessage-value-missing="invitation code is required!"
               class="form-control validate[required] text-input" 
               name="grade_name[]" id="grade_name"
               placeholder="Please Type Grade Name.." aria-describedby="basic-addon1">
        <span class="input-group-addon" id="basic-addon1" title="Please Type Grade Name" ><i class="fa  fa-adn"></i></span>
    </div>
</div>

<div class="form-group col-sm-5">
    <div class="input-group">
        <input type="number" 
               data-errormessage-value-missing="invitation code is required!"
               class="form-control validate[required, custom[integer]] text-input" 
               name="grade_number[]" id="grade_number"
               placeholder="Please Type Grade Number.." aria-describedby="basic-addon1">
        <span class="input-group-addon" id="basic-addon1" title="Please Type Grade Number" ><i class="fa  fa-qrcode"></i></span>
    </div>
</div>

<div class="form-group col-sm-2 ">
    <a href="jascript:void(0)" onclick="calcelGrade('<?php echo $grade_number; ?>', '', 'Cancel');">
        <i class="fa fa-times-circle fa-2x"></i>
    </a>
</div>