加载/重新加载页面时隐藏验证输出标记（✘）符号隐藏

Question

I use the code below with HTML5 pattern matching on the input boxes and the CSS3 :invalid and :valid pseudo-selectors to display the output of the validation (valid value or not) in the div.input-validation available next to the input box. This works as expected but it displays the validation mark (✘ - invalid input) during page load itself and on re-loading the page. How should I avoid this?

Code:

<style type="text/css">
  input {
    font-size: 1em;
    padding: .3em;
    border-radius: 3px;
    margin: .2em;
  } 
  input[type="text"]:valid {
    color: green;
  }
  input[type="text"]:valid ~ .input-validation::before {
    content: "\2714";
    color: green;
  }
  input[type="text"]:invalid ~ .input-validation::before {
    content: "\2718";
    color: red;
  }
  .input-validation {
    display: inline-block;
  } 
</style>
<?echo $passwordregister;?>
<input name="pw" autocomplete="off" type="text" id="pw" pattern="[a-zA-Z0-9]{6,22}" autofocus required >
<div class="input-validation"></div>

Answer 1

You can hide the invalid value (✘) symbol on page load using either one of the following options.

Option 1: Hide the span which contains the symbol on page load and display it only when some keypress event has happened on the input text box.

 window.onload = function() { var el = document.querySelectorAll("input[type='text']"); for (var i = 0; i < el.length; i++) { el[i].onkeypress = showSymbol; } function showSymbol() { this.nextElementSibling.style.display = "inline-block"; // display the span next to the input in which key was pressed. } } 

 input { font-size: 1em; padding: .3em; border-radius: 3px; margin: .2em; } input[type="text"]:valid { color: green; } input[type="text"]:valid + .input-validation::before { content: "\\2714"; color: green; } input[type="text"]:invalid + .input-validation::before { content: "\\2718"; color: red; } .input-validation { display: none; } 

 <input name="pw" autocomplete="off" type="text" id="pw" class="new" pattern="[a-zA-Z0-9]{6,22}" autofocus required/> <span class="input-validation"></span> 

---

Option 2: Define the CSS rules based on the presence of certain class (say visited ) and assign this class only when some key is pressed in the input box.

 window.onload = function() { var el = document.querySelectorAll("input[type='text']"); for (var i = 0; i < el.length; i++) { el[i].onkeypress = showSymbol; } function showSymbol() { this.classList.add("visited"); // add the visited class } } 

 input { font-size: 1em; padding: .3em; border-radius: 3px; margin: .2em; } input[type="text"].visited:valid { color: green; } input[type="text"].visited:valid + .input-validation::before { content: "\\2714"; color: green; } input[type="text"].visited:invalid + .input-validation::before { content: "\\2718"; color: red; } .input-validation { display: inline-block; } 

 <input name="pw" autocomplete="off" type="text" id="pw" class="new" pattern="[a-zA-Z0-9]{6,22}" autofocus required/> <span class="input-validation"></span> 

Note:

• I have replaced the ~ in your CSS selectors with + because ~ selects all siblings which match the selector whereas the + selects only the adjacent sibling. Using ~ would make the span next to all input boxes get displayed (when you have multiple input boxes in the form) as soon as you type a value in the first.
• I have also modified the .input-validation from div to span but that is more of a personal preference and you can just retain the original div itself without any difference in functionality.