Question

所以，我想在这里完成的是阻止人们进入表单的其余部分，直到他们通过隐藏最后一部分来关注第一部分，直到某个字段的值大于空。

这是我的HTML：

<div class="fieldcontainer">
<label>E-mail:</label>
<input type="email" name="email" maxlength="100" id="email" required>
</div>
<br><br>
<div id="projectinformation" style="display:none">
<h3>Project Information</h3>
<div class="fieldcontainer">
<label>Project Name:</label>
<input type="text" name="project_name" maxlength="70" required>
</div>
<br><br>
<div class="fieldcontainer">
<label>Project Number:</label>
<input type="text" name="project_number" required>
</div>
<br><br>
<div class="fieldcontainer">
<label>Business Unit:</label>
<select name="business_unit" required>
    <option>--Select--</option>
</select>
</div>
<br><br>
<div class="fieldcontainer">
<label>Project Address:</label>
<input type="text" name="address" required>
</div>
<br><br>
<div class="fieldcontainer">
<label>Number of users on site:</label>
<select id="numberofstaff">
    <option class="staffselection" value="">--Select--</option>
    <option class="staffselection" value="smalljobsite">1-3 staff</option>
    <option class="staffselection" value="mediumjobsite">4-7 staff</option>
    <option class="staffselection" value="largejobsite">8+ staff</option>
</select>
</div>
</div>

这是我的JS：

while (document.getElementById('email').value > ""){
document.getElementById('projectinformation').style.display = 'initial';
}

Answer 1

您可能想要一个事件处理程序，并检查输入值长度，然后显示表单的其余部分

document.getElementById('email').addEventListener('input', function() {
    if ( this.value.length > 0 ) {
        document.getElementById('projectinformation').style.display = 'block';
    }
}, false);

或在jQuery中

$('#email').on('input', function() {
    if (this.value.length > 0) $('#projectinformation').show();
});

Answer 2

这是jQuery解决方案：

  $("#email").keyup(function() {
      if($(this).val().length)     
         $('#projectinformation').show();
      else 
         $('#projectinformation').hide();
  });

如果您想验证它是否是有效的电子邮件然后显示表单，您可以执行以下操作：（https://stackoverflow.com/a/2855946/1845408）：

 function isValidEmailAddress(emailAddress) {
      var pattern = new RegExp(/^((([a-z]|\d|[!#\$%&'\*\+\-\/=\?\^_`{\|}~]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])+(\.([a-z]|\d|[!#\$%&'\*\+\-\/=\?\^_`{\|}~]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])+)*)|((\x22)((((\x20|\x09)*(\x0d\x0a))?(\x20|\x09)+)?(([\x01-\x08\x0b\x0c\x0e-\x1f\x7f]|\x21|[\x23-\x5b]|[\x5d-\x7e]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(\\([\x01-\x09\x0b\x0c\x0d-\x7f]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]))))*(((\x20|\x09)*(\x0d\x0a))?(\x20|\x09)+)?(\x22)))@((([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])*([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])))\.)+(([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])*([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])))\.?$/i);
      return pattern.test(emailAddress);
 };


  $("#email").keyup(function() {
      if(isValidEmailAddress($(this).val())) {    
             $('#projectinformation').show();
          else 
            $('#projectinformation').hide();
  });

如何隐藏div直到某个字段值大于空

2 个答案: