Merhabalar.
Form olayı olmadan(Çünkü wizard form kullandım, aksi takdirde bozuluyor.), Input boş bırakılırsa buton çalışmasın istiyorum. (Görünmeyebilir de, pasif hâle de getirilebilir yöntem fark etmez.) Bu işlemi nasıl yapabilirim? Yardımcı olabilecek varsa çok memnun kalırım.
Kodlar:
<div class="container-fluid">
    <div class="row justify-content-center mt-0">
        <div class="col-11 col-sm-9 col-md-7 col-lg-6 text-center p-0 mt-3 mb-2">
            <div class="card px-0 pt-4 pb-0 mt-3 mb-3">
                <h2><strong>Kayıt Ol</strong></h2>
                <p>Adımları izleyin ve "İlerle" butonuna tıklayın.</p>
                <div class="row">
                    <div class="col-md-12 mx-0">
                        <form id="msform">
                            <!-- progressbar -->
                            <ul id="progressbar">
                                <li class="active" id="account"><strong>Bağlantı</strong></li>
                                <li id="personal"><strong>Personal</strong></li>
                                <li id="payment"><strong>Payment</strong></li>
                                <li id="confirm"><strong>Finish</strong></li>
                            </ul> <!-- fieldsets -->
  
                            <fieldset>
                                <div class="form-card">
                                    <h2 class="fs-title">Kullanıcı Adınız</h2>
                                    <input type="text" name="username" placeholder="Kullanıcı Adınız" id="myText" onkeyup="stoppedTyping()" required>
                                </div> <input type="button" name="next" class="next action-button" value="İlerle" id="start_button" onclick="verify()" />
                            </fieldset>

                            <fieldset>
                                <div class="form-card">
                                    <h2 class="fs-title">Personal Information</h2> <input type="text" name="fname" placeholder="First Name" /> <input type="text" name="lname" placeholder="Last Name" /> <input type="text" name="phno" placeholder="Contact No." /> <input type="text" name="phno_2" placeholder="Alternate Contact No." />
                                </div> <input type="button" name="previous" class="previous action-button-previous" value="Previous" /> <input type="button" name="next" class="next action-button" value="Next Step" />
                            </fieldset>
                            <fieldset>
                                <div class="form-card">
                                    <h2 class="fs-title">Payment Information</h2>
                                    <div class="radio-group">
                                        <div class='radio' data-value="credit"><img src="https://i.imgur.com/XzOzVHZ.jpg" width="200px" height="100px"></div>
                                        <div class='radio' data-value="paypal"><img src="https://i.imgur.com/jXjwZlj.jpg" width="200px" height="100px"></div> <br>
                                    </div> <label class="pay">Card Holder Name*</label> <input type="text" name="holdername" placeholder="" />
                                    <div class="row">
                                        <div class="col-9"> <label class="pay">Card Number*</label> <input type="text" name="cardno" placeholder="" /> </div>
                                        <div class="col-3"> <label class="pay">CVC*</label> <input type="password" name="cvcpwd" placeholder="***" /> </div>
                                    </div>
                                    <div class="row">
                                        <div class="col-3"> <label class="pay">Expiry Date*</label> </div>
                                        <div class="col-9"> <select class="list-dt" id="month" name="expmonth">
                                                <option selected>Month</option>
                                                <option>January</option>
                                                <option>February</option>
                                                <option>March</option>
                                                <option>April</option>
                                                <option>May</option>
                                                <option>June</option>
                                                <option>July</option>
                                                <option>August</option>
                                                <option>September</option>
                                                <option>October</option>
                                                <option>November</option>
                                                <option>December</option>
                                            </select> <select class="list-dt" id="year" name="expyear">
                                                <option selected>Year</option>
                                            </select> </div>
                                    </div>
                                </div> <input type="button" name="previous" class="previous action-button-previous" value="Previous" /> <input type="button" name="make_payment" class="next action-button" value="Confirm" />
                            </fieldset>
                            <fieldset>
                                <div class="form-card">
                                    <h2 class="fs-title text-center">Success !</h2> <br><br>
                                    <div class="row justify-content-center">
                                        <div class="col-3"> <img src="https://img.icons8.com/color/96/000000/ok--v2.png" class="fit-image"> </div>
                                    </div> <br><br>
                                    <div class="row justify-content-center">
                                        <div class="col-7 text-center">
                                            <h5>You Have Successfully Signed Up</h5>
                                        </div>
                                    </div>
                                </div>
                            </fieldset>
                        </form>
                    </div>
                </div>
            </div>
        </div>
    </div>
</div>
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