Javascript Archives

Hash Link Offset

When you have a hash link on your page ( href=”#target” ) sometimes the browser scrolls too low and cuts off or puts too close to the top the target element.

You can offset this hash link by hooking into the ‘hashchange’ event.

// Allow a hash link to move X pixels above the target location
// https://stackoverflow.com/questions/17534661/make-anchor-link-go-some-pixels-above-where-its-linked-to
window.addEventListener("hashchange", function () {
	window.scrollTo(window.scrollX, window.scrollY - 100);
});

// Allow a hash link to move X pixels above the target location

// https://stackoverflow.com/questions/17534661/make-anchor-link-go-some-pixels-above-where-its-linked-to

window.addEventListener("hashchange", function () {

window.scrollTo(window.scrollX, window.scrollY - 100);

});

This does NOT resolve linking directly to this hash tag, but will fix the on page hash link.

To do that you can setup the following functions.

// The function actually applying the offset
function offsetAnchor() {
  if (location.hash.length !== 0) {
    window.scrollTo(window.scrollX, window.scrollY - 100);
  }
}

// Captures click events of all <a> elements with href starting with #
$(document).on('click', 'a[href^="#"]', function(event) {
  // Click events are captured before hashchanges. Timeout
  // causes offsetAnchor to be called after the page jump.
  window.setTimeout(function() {
    offsetAnchor();
  }, 0);
});

// Set the offset when entering page with hash present in the url
window.setTimeout(offsetAnchor, 0);

// The function actually applying the offset

function offsetAnchor() {

if (location.hash.length !== 0) {

window.scrollTo(window.scrollX, window.scrollY - 100);

}

// Captures click events of all <a> elements with href starting with #

$(document).on('click', 'a[href^="#"]', function(event) {

// Click events are captured before hashchanges. Timeout

// causes offsetAnchor to be called after the page jump.

window.setTimeout(function() {

offsetAnchor();

}, 0);

});

// Set the offset when entering page with hash present in the url

window.setTimeout(offsetAnchor, 0);

Thanks to Eric Olsen over at stack overflow!

I recently needed to update a form to update through AJAX so the page didn’t reload when submitted. The issue was that we had some images on this form. In the past I have used things like plupload, but that didn’t seem like the right approach in this instance.

At first I looked into the “fetch” api and saw a good post from Tania Rascia, but unfortunately the fetch API still isn’t fully adopted…DAMN YOU MICROSOFT!

Thankfully I was able to find a jQuery version of this same idea over on Makeitweb.com by Yogesh Singh.

I also needed to make sure I sent along post data with the FormData to update the rest of the form. Here is an example of the JS code I ended up using:

var $agentEditForm = $('#agent-edit-form');
$agentEditForm.submit(function(e){
	e.preventDefault();
        
        //disable our button so we don't submit twice
	$(this).find('button.save-form').prop('disabled', true);
        
        // Serialize our form into a usable object
	var formData = $(this).serializeObject();
        //our PHP script we are sending the info to
	var url = '/update-agent.php';
        //Create a FormData object
	var fd = new FormData();
        //get the files from our input[type=file]
	var files = $('#profile-image')[0].files[0];
        //if someone as uploaded an image let's attach it to our formdata
	if(files){
		fd.append('profile_image',files);
	}

	// Unfortunately we cannot attach an object to our form data, so lets loop through our formData and attach our variables
	for(var propertyName in formData) {
		fd.append(propertyName,formData[propertyName]);
	}

        // Send our data off to our server script
	$.ajax({
		url: url,
		type: 'post',
		data: fd,
		contentType: false,
		processData: false,
		success: function(response){

			if(response != 0){
				//success
			}else{
				//fail
			}
                        
                        // Remember to re-enable our submit button 
			$agentEditForm.find('button.save-form').prop('disabled', false);
		},
	});

	return false;
});

var $agentEditForm = $('#agent-edit-form');

$agentEditForm.submit(function(e){

e.preventDefault();

//disable our button so we don't submit twice

$(this).find('button.save-form').prop('disabled', true);

// Serialize our form into a usable object

var formData = $(this).serializeObject();

//our PHP script we are sending the info to

var url = '/update-agent.php';

//Create a FormData object

var fd = new FormData();

//get the files from our input[type=file]

var files = $('#profile-image')[0].files[0];

//if someone as uploaded an image let's attach it to our formdata

if(files){

fd.append('profile_image',files);

}

// Unfortunately we cannot attach an object to our form data, so lets loop through our formData and attach our variables

for(var propertyName in formData) {

fd.append(propertyName,formData[propertyName]);

}

// Send our data off to our server script

$.ajax({

url: url,

type: 'post',

data: fd,

contentType: false,

processData: false,

success: function(response){

if(response != 0){

//success

}else{

//fail

}

// Remember to re-enable our submit button

$agentEditForm.find('button.save-form').prop('disabled', false);

});

return false;

});

On the server script you can access this data just like any other form submission.

PHP

print_r($_FILES);
print_r($_POST);

1 2	print_r($_FILES); print_r($_POST);

There we go! Now we can submit our form, including images, to our server script!

NOTE: We are using a custom function to serialize our form data. You can find that function here.

Cross Browser HTML5 Date Input

I have been waiting for the day when using <input type=”date” /> would be common…alas, 3 years after the standards were written it is still not supported in IE or Safari.

UNFORTUNATELY we still have to support these browsers…

Traditionally I have been using a third party datepicker (jQuery UI, Bootstrap Datepicker, etc) but I REALLY wanted to just use the default type=”date” this time.

I found a great solution over on Stack Overflow from Kashif Latif.

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.3/jquery.min.js"></script>
<script src="http://cdn.jsdelivr.net/webshim/1.12.4/extras/modernizr-custom.js"></script>
<script src="http://cdn.jsdelivr.net/webshim/1.12.4/polyfiller.js"></script>
<script>
  webshims.setOptions('waitReady', false);
  webshims.setOptions('forms-ext', {type: 'date'});
  webshims.setOptions('forms-ext', {type: 'time'});
  webshims.polyfill('forms forms-ext');
</script>

webshims.setOptions('waitReady', false);

webshims.setOptions('forms-ext', {type: 'date'});

webshims.setOptions('forms-ext', {type: 'time'});

webshims.polyfill('forms forms-ext');

</script>

BAM! We have a polyfill. As far as I can tell this does the trick.

Helpful Javascript Prototype Functions

Sometimes the built in functionality for various Javascript primitives is not enough. Here is an assortment of useful Prototype functions. Enjoy!

/**
 * Clean all non numeric characters. Also keeping "."
 * usage: str.cleanNumber()
 */
String.prototype.cleanNumber = function() {

	var returnValue = this.replace(/[^0-9.-]/g,'');

	//let's make sure we do not return a NaN value
	if(isNaN(returnValue) || returnValue == ""){
		returnValue = 0;
	}

    return returnValue;
}


/**
 * Create a default string function to allow replacing all characters in a string
 */
String.prototype.replaceAll = function(search, replacement) {
	return this.replace(new RegExp(search, 'g'), replacement);
};


/**
 * Format a float as currency
 * usage: floatvalue.formatMoney(0, '.', ',');
 */
Number.prototype.formatMoney = function(c, d, t){
  var n = this, 
      c = isNaN(c = Math.abs(c)) ? 2 : c, 
      d = d == undefined ? "." : d, 
      t = t == undefined ? "," : t, 
      s = n < 0 ? "-" : "", 
      i = parseInt(n = Math.abs(+n || 0).toFixed(c)) + "", 
      j = (j = i.length) > 3 ? j % 3 : 0;
     return s + (j ? i.substr(0, j) + t : "") + i.substr(j).replace(/(\d{3})(?=\d)/g, "$1" + t) + (c ? d + Math.abs(n - i).toFixed(c).slice(2) : "");
   };

/**

* Clean all non numeric characters. Also keeping "."

* usage: str.cleanNumber()

String.prototype.cleanNumber = function() {

var returnValue = this.replace(/[^0-9.-]/g,'');

//let's make sure we do not return a NaN value

if(isNaN(returnValue) || returnValue == ""){

returnValue = 0;

}

return returnValue;

}

/**

* Create a default string function to allow replacing all characters in a string

String.prototype.replaceAll = function(search, replacement) {

return this.replace(new RegExp(search, 'g'), replacement);

};

/**

* Format a float as currency

* usage: floatvalue.formatMoney(0, '.', ',');

Number.prototype.formatMoney = function(c, d, t){

var n = this,

c = isNaN(c = Math.abs(c)) ? 2 : c,

d = d == undefined ? "." : d,

t = t == undefined ? "," : t,

s = n < 0 ? "-" : "",

i = parseInt(n = Math.abs(+n || 0).toFixed(c)) + "",

j = (j = i.length) > 3 ? j % 3 : 0;

return s + (j ? i.substr(0, j) + t : "") + i.substr(j).replace(/(\d{3})(?=\d)/g, "$1" + t) + (c ? d + Math.abs(n - i).toFixed(c).slice(2) : "");

};

JS Capitalize a String

Just a simple String prototype to capitalize the first letter of the string.

/**
 * Capitalize the first letter of a string
 * usage: str.capitalize()
 */
String.prototype.capitalize = function() {
	return this.charAt(0).toUpperCase() + this.slice(1);
}

/**

* Capitalize the first letter of a string

* usage: str.capitalize()

String.prototype.capitalize = function() {

return this.charAt(0).toUpperCase() + this.slice(1);

}

Convert Form to JS Object

This function will take your entire HTML form and convert all the inputs into a single JS object! Thanks to Dave over at Stack Overflow!

/**
 * Take a form and convert it into a Object for easy manipulation
 * 
 * @link https://stackoverflow.com/a/23315254
 * @link http://jsfiddle.net/akhildave/sxGtM/5002/
 */
$.fn.serializeObject = function() {
	var o = {};
	var a = this.serializeArray();
	$.each(a, function() {
		if (o[this.name] !== undefined) {
			if (!o[this.name].push) {
				o[this.name] = [o[this.name]];
			}
			o[this.name].push(this.value || '');
		} else {
			o[this.name] = this.value || '';
		}
	});
	return o;
};

/**

* Take a form and convert it into a Object for easy manipulation

* @link https://stackoverflow.com/a/23315254

* @link http://jsfiddle.net/akhildave/sxGtM/5002/

$.fn.serializeObject = function() {

var o = {};

var a = this.serializeArray();

$.each(a, function() {

if (o[this.name] !== undefined) {

if (!o[this.name].push) {

o[this.name] = [o[this.name]];

}

o[this.name].push(this.value || '');

} else {

o[this.name] = this.value || '';

}

});

return o;

};

Usage is as simple as:

var formObject= $(‘form’).serializeObject();

Requires jQuery

Category: Javascript

Hash Link Offset

Upload Images Using JS

Cross Browser HTML5 Date Input

Helpful Javascript Prototype Functions

JS Capitalize a String

Convert Form to JS Object