Simple validation query

[quartzy]

I have a simple validation script. The first line of the validation is:

function Validate()
{
if (document.form.name.value == '')
{

the id of my form is form, so my query is will this validation work, as it does not have a name but it has an id. Should I change the name (above) to id?

[chump2877]

Without a "name" for your form, that code won't work. I would use a name for your form that is identical to the form's id.

Also, in general, you should avoid using an "id" or "name" that also refers to an element or attribute in the DOM.

So, putting the two ideas together, try something like this:

In your HTML:

<form id="form1" name="form1" method="post" action="file.php">
   <p>Username: <input type="text" name="username" /></p>
</form>

In your JS:

if (document.form1.username.value == '')

[quartzy]

Thanks for your post, I did wonder about that small thing.

[Philip M]

Form validation of the pattern if (document.form1.username.value == '') is barely worthy of the name, and virtually useless, as even a single space, an X or a ? will return false, that is pass the validation. Numeric values, such as zip codes and phone numbers, should be validated as such. Ditto email addresses. This topic has been covered many times before in this forum.


All advice is supplied packaged by intellectual weight, and not by volume. Contents may settle slightly in transit.

[quartzy]

Sorry I do not fully understand you, are you saying that my code is not going to work? I am not a regular member of this forum, so would not know if the validation has been covered many times either. I could delve into regular expressions but it is just for a simple form, and so would work OK I feel. with fields of name email and message.

[Philip M]

Read what I said. You code will work, but is virtually useless as if the user enters even a single space or a ? sign it will pass the validation.

You can use the search feature of this forum to find out more about how to validate form fields.

Originally Posted by quartzy

I am not a regular member of this forum

639 posts and not a regular user?

[bullant]

Hi quartzy,

I usually do something along these lines for my client side validation. Instead of alerting the errors, another option is to highlight the input labels in the form with a different colour, typically red.

 
            function validateForm(){
                var inp1 = document.getElementById('txtInp1').value;
                //... similarly for other inputs to be validated
                var errMsg = "The following inputs are invalid:\n\n"
                var errors = new Array();
                var isDataValid = true;
                //validate inp1
                if(/[^0-9]/.test(inp1)){
                    isDataValid = false;
                    errors.push('inp1');
                }
                //validate the other inputs
                //...
                //display any error messages
                if(!isDataValid){
                    for(i=0; i < errors.length; i++){
                        errMsg += errors[i] + "\n";
                    }
                    alert(errMsg);
                }
                return isDataValid;
            }