JavaScript form textbox value detection not working correctly.

[Jacbey]

Hi there,

 

I began making a login form for a website and decided that I wanted the registration and login form to be integrated so I made this:

 

<form method="post" action="" name="log_reg_form" id="log_reg_form">
							<table>
								<tr>
									<td>
							<table id="form_tables">
								<tr>
									<td>
										Email:
									</td>
									<td>
										<input type="text" name="email" id="email" class="textbox" />
									</td>
								</tr>
								<tr>
									<td>
										Password: 
									</td>
									<td>
										<input type="password" name="password" id="password" class="textbox" />
									</td>
								</tr>
							</table>
							<table id="other_half_of_login_form" style="opacity: 0.5; filter:alpha(opacity=50);">
								<tr>
									<td>
										Forename:
									</td>
									<td>
										<input type="text" name="forename" id="forename" class="textbox" onfocus="form_fade();" onblur="form_fadeout();" />
									</td>
								</tr>
								<tr>
									<td>
										Surname:
									</td>
									<td>
										<input type="text" name="surname" id="surname" class="textbox" onfocus="form_fade();" onblur="form_fadeout();" />
									</td>
								</tr>
								<tr>
									<td >
										<input type="radio" name="sex" id="sex1" value="male" class="gender_box" onfocus="form_fade();" onblur="form_fadeout();" /> <label for="sex1"> Male </label>
									</td>
									<td>
										<input type="radio" name="sex" id="sex2" value="female" class="gender_box" onfocus="form_fade();" onblur="form_fadeout();" /> <label for="sex2"> Female </label>
									</td>
								</tr>
								<tr>
									<td>
										Country:
									</td>
									<td>
										<select name="country" class="country_select_class" onfocus="form_fade();" onblur="form_fadeout();"> 
										<option value="" selected="selected">Select Country</option> 
										<option value="United States">United States</option> 
										<option value="United Kingdom">United Kingdom</option> 
										<option value="Afghanistan">Afghanistan</option> 
										<option value="Albania">Albania</option> 
										<option value="Algeria">Algeria</option> 
										<option value="American Samoa">American Samoa</option> 
										<option value="Andorra">Andorra</option> 
										<option value="Angola">Angola</option> 
										<option value="Anguilla">Anguilla</option> 
										<option value="Antarctica">Antarctica</option> 
										<option value="Antigua and Barbuda">Antigua and Barbuda</option> 
										<option value="Argentina">Argentina</option> 
										<option value="Armenia">Armenia</option> 
										<option value="Aruba">Aruba</option> 
										<option value="Australia">Australia</option> 
										<option value="Austria">Austria</option> 
										<option value="Azerbaijan">Azerbaijan</option> 
										<option value="Bahamas">Bahamas</option> 
										<option value="Bahrain">Bahrain</option> 
										<option value="Bangladesh">Bangladesh</option> 
										<option value="Barbados">Barbados</option> 
										<option value="Belarus">Belarus</option> 
										<option value="Belgium">Belgium</option> 
										<option value="Belize">Belize</option> 
										<option value="Benin">Benin</option> 
										<option value="Bermuda">Bermuda</option> 
										<option value="Bhutan">Bhutan</option> 
										<option value="Bolivia">Bolivia</option> 
										<option value="Bosnia and Herzegovina">Bosnia and Herzegovina</option> 
										<option value="Botswana">Botswana</option> 
										<option value="Bouvet Island">Bouvet Island</option> 
										<option value="Brazil">Brazil</option> 
										<option value="British Indian Ocean Territory">British Indian Ocean Territory</option> 
										<option value="Brunei Darussalam">Brunei Darussalam</option> 
										<option value="Bulgaria">Bulgaria</option> 
										<option value="Burkina Faso">Burkina Faso</option> 
										<option value="Burundi">Burundi</option> 
										<option value="Cambodia">Cambodia</option> 
										<option value="Cameroon">Cameroon</option> 
										<option value="Canada">Canada</option> 
										<option value="Cape Verde">Cape Verde</option> 
										<option value="Cayman Islands">Cayman Islands</option> 
										<option value="Central African Republic">Central African Republic</option> 
										<option value="Chad">Chad</option> 
										<option value="Chile">Chile</option> 
										<option value="China">China</option> 
										<option value="Christmas Island">Christmas Island</option> 
										<option value="Cocos (Keeling) Islands">Cocos (Keeling) Islands</option> 
										<option value="Colombia">Colombia</option> 
										<option value="Comoros">Comoros</option> 
										<option value="Congo">Congo</option> 
										<option value="Congo, The Democratic Republic of The">Congo, The Democratic Republic of The</option> 
										<option value="Cook Islands">Cook Islands</option> 
										<option value="Costa Rica">Costa Rica</option> 
										<option value="Cote D'ivoire">Cote D'ivoire</option> 
										<option value="Croatia">Croatia</option> 
										<option value="Cuba">Cuba</option> 
										<option value="Cyprus">Cyprus</option> 
										<option value="Czech Republic">Czech Republic</option> 
										<option value="Denmark">Denmark</option> 
										<option value="Djibouti">Djibouti</option> 
										<option value="Dominica">Dominica</option> 
										<option value="Dominican Republic">Dominican Republic</option> 
										<option value="Ecuador">Ecuador</option> 
										<option value="Egypt">Egypt</option> 
										<option value="El Salvador">El Salvador</option> 
										<option value="Equatorial Guinea">Equatorial Guinea</option> 
										<option value="Eritrea">Eritrea</option> 
										<option value="Estonia">Estonia</option> 
										<option value="Ethiopia">Ethiopia</option> 
										<option value="Falkland Islands (Malvinas)">Falkland Islands (Malvinas)</option> 
										<option value="Faroe Islands">Faroe Islands</option> 
										<option value="Fiji">Fiji</option> 
										<option value="Finland">Finland</option> 
										<option value="France">France</option> 
										<option value="French Guiana">French Guiana</option> 
										<option value="French Polynesia">French Polynesia</option> 
										<option value="French Southern Territories">French Southern Territories</option> 
										<option value="Gabon">Gabon</option> 
										<option value="Gambia">Gambia</option> 
										<option value="Georgia">Georgia</option> 
										<option value="Germany">Germany</option> 
										<option value="Ghana">Ghana</option> 
										<option value="Gibraltar">Gibraltar</option> 
										<option value="Greece">Greece</option> 
										<option value="Greenland">Greenland</option> 
										<option value="Grenada">Grenada</option> 
										<option value="Guadeloupe">Guadeloupe</option> 
										<option value="Guam">Guam</option> 
										<option value="Guatemala">Guatemala</option> 
										<option value="Guinea">Guinea</option> 
										<option value="Guinea-bissau">Guinea-bissau</option> 
										<option value="Guyana">Guyana</option> 
										<option value="Haiti">Haiti</option> 
										<option value="Heard Island and Mcdonald Islands">Heard Island and Mcdonald Islands</option> 
										<option value="Holy See (Vatican City State)">Holy See (Vatican City State)</option> 
										<option value="Honduras">Honduras</option> 
										<option value="Hong Kong">Hong Kong</option> 
										<option value="Hungary">Hungary</option> 
										<option value="Iceland">Iceland</option> 
										<option value="India">India</option> 
										<option value="Indonesia">Indonesia</option> 
										<option value="Iran, Islamic Republic of">Iran, Islamic Republic of</option> 
										<option value="Iraq">Iraq</option> 
										<option value="Ireland">Ireland</option> 
										<option value="Israel">Israel</option> 
										<option value="Italy">Italy</option> 
										<option value="Jamaica">Jamaica</option> 
										<option value="Japan">Japan</option> 
										<option value="Jordan">Jordan</option> 
										<option value="Kazakhstan">Kazakhstan</option> 
										<option value="Kenya">Kenya</option> 
										<option value="Kiribati">Kiribati</option> 
										<option value="Korea, Democratic People's Republic of">Korea, Democratic People's Republic of</option> 
										<option value="Korea, Republic of">Korea, Republic of</option> 
										<option value="Kuwait">Kuwait</option> 
										<option value="Kyrgyzstan">Kyrgyzstan</option> 
										<option value="Lao People's Democratic Republic">Lao People's Democratic Republic</option> 
										<option value="Latvia">Latvia</option> 
										<option value="Lebanon">Lebanon</option> 
										<option value="Lesotho">Lesotho</option> 
										<option value="Liberia">Liberia</option> 
										<option value="Libyan Arab Jamahiriya">Libyan Arab Jamahiriya</option> 
										<option value="Liechtenstein">Liechtenstein</option> 
										<option value="Lithuania">Lithuania</option> 
										<option value="Luxembourg">Luxembourg</option> 
										<option value="Macao">Macao</option> 
										<option value="Macedonia, The Former Yugoslav Republic of">Macedonia, The Former Yugoslav Republic of</option> 
										<option value="Madagascar">Madagascar</option> 
										<option value="Malawi">Malawi</option> 
										<option value="Malaysia">Malaysia</option> 
										<option value="Maldives">Maldives</option> 
										<option value="Mali">Mali</option> 
										<option value="Malta">Malta</option> 
										<option value="Marshall Islands">Marshall Islands</option> 
										<option value="Martinique">Martinique</option> 
										<option value="Mauritania">Mauritania</option> 
										<option value="Mauritius">Mauritius</option> 
										<option value="Mayotte">Mayotte</option> 
										<option value="Mexico">Mexico</option> 
										<option value="Micronesia, Federated States of">Micronesia, Federated States of</option> 
										<option value="Moldova, Republic of">Moldova, Republic of</option> 
										<option value="Monaco">Monaco</option> 
										<option value="Mongolia">Mongolia</option> 
										<option value="Montserrat">Montserrat</option> 
										<option value="Morocco">Morocco</option> 
										<option value="Mozambique">Mozambique</option> 
										<option value="Myanmar">Myanmar</option> 
										<option value="Namibia">Namibia</option> 
										<option value="Nauru">Nauru</option> 
										<option value="Nepal">Nepal</option> 
										<option value="Netherlands">Netherlands</option> 
										<option value="Netherlands Antilles">Netherlands Antilles</option> 
										<option value="New Caledonia">New Caledonia</option> 
										<option value="New Zealand">New Zealand</option> 
										<option value="Nicaragua">Nicaragua</option> 
										<option value="Niger">Niger</option> 
										<option value="Nigeria">Nigeria</option> 
										<option value="Niue">Niue</option> 
										<option value="Norfolk Island">Norfolk Island</option> 
										<option value="Northern Mariana Islands">Northern Mariana Islands</option> 
										<option value="Norway">Norway</option> 
										<option value="Oman">Oman</option> 
										<option value="Pakistan">Pakistan</option> 
										<option value="Palau">Palau</option> 
										<option value="Palestinian Territory, Occupied">Palestinian Territory, Occupied</option> 
										<option value="Panama">Panama</option> 
										<option value="Papua New Guinea">Papua New Guinea</option> 
										<option value="Paraguay">Paraguay</option> 
										<option value="Peru">Peru</option> 
										<option value="Philippines">Philippines</option> 
										<option value="Pitcairn">Pitcairn</option> 
										<option value="Poland">Poland</option> 
										<option value="Portugal">Portugal</option> 
										<option value="Puerto Rico">Puerto Rico</option> 
										<option value="Qatar">Qatar</option> 
										<option value="Reunion">Reunion</option> 
										<option value="Romania">Romania</option> 
										<option value="Russian Federation">Russian Federation</option> 
										<option value="Rwanda">Rwanda</option> 
										<option value="Saint Helena">Saint Helena</option> 
										<option value="Saint Kitts and Nevis">Saint Kitts and Nevis</option> 
										<option value="Saint Lucia">Saint Lucia</option> 
										<option value="Saint Pierre and Miquelon">Saint Pierre and Miquelon</option> 
										<option value="Saint Vincent and The Grenadines">Saint Vincent and The Grenadines</option> 
										<option value="Samoa">Samoa</option> 
										<option value="San Marino">San Marino</option> 
										<option value="Sao Tome and Principe">Sao Tome and Principe</option> 
										<option value="Saudi Arabia">Saudi Arabia</option> 
										<option value="Senegal">Senegal</option> 
										<option value="Serbia and Montenegro">Serbia and Montenegro</option> 
										<option value="Seychelles">Seychelles</option> 
										<option value="Sierra Leone">Sierra Leone</option> 
										<option value="Singapore">Singapore</option> 
										<option value="Slovakia">Slovakia</option> 
										<option value="Slovenia">Slovenia</option> 
										<option value="Solomon Islands">Solomon Islands</option> 
										<option value="Somalia">Somalia</option> 
										<option value="South Africa">South Africa</option> 
										<option value="South Georgia and The South Sandwich Islands">South Georgia and The South Sandwich Islands</option> 
										<option value="Spain">Spain</option> 
										<option value="Sri Lanka">Sri Lanka</option> 
										<option value="Sudan">Sudan</option> 
										<option value="Suriname">Suriname</option> 
										<option value="Svalbard and Jan Mayen">Svalbard and Jan Mayen</option> 
										<option value="Swaziland">Swaziland</option> 
										<option value="Sweden">Sweden</option> 
										<option value="Switzerland">Switzerland</option> 
										<option value="Syrian Arab Republic">Syrian Arab Republic</option> 
										<option value="Taiwan, Province of China">Taiwan, Province of China</option> 
										<option value="Tajikistan">Tajikistan</option> 
										<option value="Tanzania, United Republic of">Tanzania, United Republic of</option> 
										<option value="Thailand">Thailand</option> 
										<option value="Timor-leste">Timor-leste</option> 
										<option value="Togo">Togo</option> 
										<option value="Tokelau">Tokelau</option> 
										<option value="Tonga">Tonga</option> 
										<option value="Trinidad and Tobago">Trinidad and Tobago</option> 
										<option value="Tunisia">Tunisia</option> 
										<option value="Turkey">Turkey</option> 
										<option value="Turkmenistan">Turkmenistan</option> 
										<option value="Turks and Caicos Islands">Turks and Caicos Islands</option> 
										<option value="Tuvalu">Tuvalu</option> 
										<option value="Uganda">Uganda</option> 
										<option value="Ukraine">Ukraine</option> 
										<option value="United Arab Emirates">United Arab Emirates</option> 
										<option value="United Kingdom">United Kingdom</option> 
										<option value="United States">United States</option> 
										<option value="United States Minor Outlying Islands">United States Minor Outlying Islands</option> 
										<option value="Uruguay">Uruguay</option> 
										<option value="Uzbekistan">Uzbekistan</option> 
										<option value="Vanuatu">Vanuatu</option> 
										<option value="Venezuela">Venezuela</option> 
										<option value="Viet Nam">Viet Nam</option> 
										<option value="Virgin Islands, British">Virgin Islands, British</option> 
										<option value="Virgin Islands, U.S.">Virgin Islands, U.S.</option> 
										<option value="Wallis and Futuna">Wallis and Futuna</option> 
										<option value="Western Sahara">Western Sahara</option> 
										<option value="Yemen">Yemen</option> 
										<option value="Zambia">Zambia</option> 
										<option value="Zimbabwe">Zimbabwe</option>
										</select>
									</td>
								</tr>
								</table>
								<table id="log_reg_form_button">
								<tr>
									<td>
										 
									</td>
									<td>
										<input type="submit" name="submit" id="submit" class="textbox_button" value="Login" />
									</td>
								</tr>
							</table>
							</td>
							</tr>
							</table>
						</form>

 

Then I decided I wanted only the email and password bit to be visible and the rest just a bit faded out but when you go onto the next box if you haven't got an account it makes the rest of the form visible. Now, I got that working alright but then I noticed when you took focus off the boxes each time it would dim them out again. Then I got stuck. This is the javascript I have so far to prevent it but it doesn't work. It only works for one box at a time. Meaning, if the forename box is filled out it won't dim it if you take the focus off the box however if only the surname box is filled out and you take the focus off the box it will dim the form again. This is the code I have so far:

 

<script type="text/javascript">

	function form_fade(){
		document.getElementById("other_half_of_login_form").style.opacity='1.0';
		document.log_reg_form.submit.value = "Register";
	}

	function form_fadeout(){
		if (log_reg_form.forename.value == "" || log_reg_form.surname.value == "" || log_reg_form.sex.value == "" || log_reg_form.country.value == "Select Country")
		{
			document.log_reg_form.submit.value = "Login";
			document.getElementById("other_half_of_login_form").style.opacity='0.4';
		}
		else{
			document.log_reg_form.submit.value = "Register";
			document.getElementById("other_half_of_login_form").style.opacity='1.0';
		}


	}

</script>

 

I hope anyone can understand this jumbled mess of words and help me out a bit?

 

Many thanks, Jacbey.

[Adam]

So it's clear, on what events on what inputs do you want the dim effect to be removed?

[Jacbey]

Sorry, I didn't explain that enough it was quite late.

 

Okay, I want the dim effect to be removed when you've got focus on any of these: forename, surname, sex, country. If a value has been selected or has been inputed into one I want the dim effect to stay removed if you take the focus off. If nothing has been inputed or selected and you take the focus of I want it to put the dim back. I hope that makes better sense.  :-\

 

J.

[Adam]

Yeah that makes a lot more sense, cheers. Rather than adding a bunch of "onblur" and "onfocus" attributes within the HTML, we can pull out the logic and handle the binds separately. That way we can also avoid a lot of repetition by actually scripting it:

 

// Create an array of elements
var elements = [
    document.getElementById('forename'),
    document.getElementById('surname'),
    document.getElementById('sex'),
    document.getElementById('country')
];

// Loop through each element
for (i=0, l=elements.length; i<l; i++) {

    // Bind the focus event
    elements[i].onfocus = function() {

        // We always want the dim effect hidden when focusing on an element
        toggleDim(false);

    };

    // Bind the blur event
    elements[i].onblur = function() {

        var showDim = true;

        // Loop through the elements until we find one with a value
        for (x=0; x<l; x++) {
            if (elements[i].value !== '') {
                showDim = false;
                break;
            }
        }

        toggleDim(showDim);

    };
}

function toggleDim(show) {
    // I'll leave this to you
}

 

That probably looks more complicated than it is. All it does it create an array of elements, loops through them and binds the focus and blur events to each element separately. Within the focus event we simply just hide the dim effect, within the blur event we loop through the elements again and check if any have a value. When an input is encountered that does have a value we just update the flag and break out of the loop. At the end we then just update the dim.

 

I left the toggleDim() function for you to complete because that's pretty straight-forward.

 

I'm not sure how you've got your scripts set-up, but you'll need to put that at the end of the <body> or within the window's load/ready event handler.

 

---------------

 

Also I'm not sure if you've used jQuery before, but this is the kind of thing it excels at. Here's the equivalent:

 

// Create an array of elements
var elements = $('#forename, #surname, #sex, #country');

// Bind the focus/blur events
elements.focus(function() {

    // We always want the dim effect hidden when focusing on an element
    toggleDim(false);

}).blur(function() {

    var showDim = true;

    // Loop through the elements until we find one with a value
    $.each(elements, function(key, val) {
        if (val !== '') {
            showDim = false;
            return false;
        }
    });

    toggleDim(showDim);

});

 

None of this has been tested by the way.

[Adam]

Just realised there's a bug in the code. The jQuery each should use the alternative syntax and access the value with the Val() method. I'm on the train at the moment but will update the code when I'm home.

[Adam]

Fixed jQuery version:

 

// Create an array of elements
var elements = $('#forename, #surname, #sex, #country');

// Bind the focus/blur events
elements.focus(function() {

    // We always want the dim effect hidden when focusing on an element
    toggleDim(false);

}).blur(function() {

    var showDim = true;

    // Loop through the elements until we find one with a value
    elements.each(function() {
        if ($(this).val() !== '') {
            showDim = false;
            return false;
        }
    });

    toggleDim(showDim);

});