How to show setCustomValidity message/tooltip with

问题:

I'm using forms basic validation to check if email is correct format, then the data is sent by Ajax where it checks if email address is already in use and did the user select country/state or left default values in select boxes.

But for HTML5 form validation to be done submit event is needed, upon clicking submit if it passes that basic form validation Ajax operation is performed, but then when results come in I would like to use the same browser tooltips for interface consistency (and well I like how they look).

So is there a way to make them show up, I was unable to find if there is some special event for them or something like firing submit event but stopping it right away. Right now the field only gets a red edge and error message appears on hovering mouse over it, while the tooltip shows on again clicking submit button.

Also for browsers that don't have native tooltips(in my case Safari) I'm using Webshims Lib and it acts exactly the same as in Chrome and Firefox.

回答1:

I thought .checkValidity() would do the trick, but it doesn't trigger the UI.

It sounds like .reportValidity() is going to do what you want. http://www.whatwg.org/specs/web-apps/current-work/multipage/association-of-controls-and-forms.html#dom-cva-reportvalidity

I don't know if any browsers implement it yet though :/

回答2:

You can find an answer at this link: How to force a html5 form validation without submitting it via jQuery

Basically, you find a submit button and call click on it:

// force form validation
document.getElementById("submitbutton").click()

You can also change validation message after checking if email address is in use or not and then force form validation as above:

document.getElementById("email").setCustomValidity("This email is already registered!");
document.getElementById("submitbutton").click()

回答3:

It's actually very simple - add a hidden input element to your form:

<input type="hidden" id="myFormCheck" required="true" value=""/>

Call myInputField.setCustomValidity(message) on the input element you want to create a custom tooltip on then call your form.click();

The form validity process runs and displays the message popup over that element, but the form won't submit because of the hidden element, so you won't need to catch and cancel the submit event.

When you're done and really ready to go, set a value on the hidden element and the form will submit normally.

This way you can use the form tooltip for something like checking for usernames that are available, or matching any value over an HTTP Request etc.

回答4:

A polyfill for HTMLFormElement.reportValidity().
Tested with IE11 and Edge. But when running in the StackOverflow sandbox below with IE11, the validation messages are not displayed.

function reportValidityPolyfill() {
  const button = createInvisibleSubmitButton();
  this.appendChild(button);
  this.addEventListener("submit", submitEventHandler);
  var isValid = false;
  button.click();
  this.removeEventListener("submit", submitEventHandler);
  this.removeChild(button);
  return isValid;

  function createInvisibleSubmitButton() {
    const button = document.createElement("button");
    button.type = "submit";
    button.style.display = "none";
    return button;
  }

  function submitEventHandler(event) {
    event.preventDefault();
    isValid = true;
  }
}

if (!HTMLFormElement.prototype.reportValidity) {
  HTMLFormElement.prototype.reportValidity = reportValidityPolyfill;
  console.log("ReportValidity polyfill installed.");
} else {
  console.log("ReportValidity polyfill skipped.");
}

input {
  outline: 1px solid #0f0;
}

input:invalid {
  outline: 1px solid #f00;
}

<form id="form1">
  Enter a number from 1 to 5: <input type="number" min="1" max="5" required>
</form>
<br>
<div onclick="console.log('Validity: ' + document.getElementById('form1').reportValidity())">
  Click here to call reportValidity()
</div>

回答5:

Checkout this link ( Provide custom validation messages using setCustomValidity in HTML 5 pages ).

In the above link, he used "input" type is number and oninput he called the validation function. Let me know is this what you are looking for.

<input type="number" required="true" value="50" min="18" max="60" step="1" oninput="validate(this)">

回答6:

As most people say you have to use input.setCustomValidity("message").

The problem here is that you can't check that validation within the submit event, since you need to do an ajax call and then set setCustomValidity asynchronously.

So basically you have to use the change event of the input field and make the ajax call on every change. Or remove the submit button and use the click event of a normal button, check the unique email in the ajax call and then call submit through javascript.

See an example of the last option using jQuery:

<form action="/sign-in" id="form">
    <input type="email" id="email" required/>
    <button id="submit">Submit</button>
</form>

// we capture the click instead the submit
$("#submit").on("click",function(){
    var $elem = $("#email");
    var email = $elem.val();

    //the ajax call returns true if the email exists
    $.get( "ajax/checkUniqueEmail", function(data) {
        if(data === "true"){
            $elem.setCustomValidity("This email already exists.");
        }else{
            $elem.setCustomValidity("")
        }
        //then we submit the form
        $("#form").submit();
    });
});

回答7:

You can use setCustomValidity with for the element if the condition is false ( you can do it inside any event handler such as keypress or click ). If the input is NOT valid, SUBMIT. This will trigger the browser's message tooltip.

回答8:

Here's a nice live example that custom validates/gives feedback on a form input.

The basic javascript looks like:

function checkPasscode() {
    var passcode_input = document.querySelector("#passcode");

    if (passcode_input.value != "Ivy") {
        passcode_input.setCustomValidity("Wrong. It's 'Ivy'.");
    } else {
        passcode_input.setCustomValidity(""); // be sure to leave this empty!
        alert("Correct!");
    }
}

HTML:

<form>
    <label for="passcode">Enter Passcode:</label>
    <input id="passcode" 
           type="password" 
           placeholder="Your passcode" 
           oninput="checkPasscode();"
           required/>
    <button type="submit">Submit</button>
</form>