Angularjs Tricks

We define a directive that will automatically slash the input field as user typein the date. The directive have following capabiltiy: The directive will append slash '/' when input field has 2 or 5 characters. The input will accept only 10 characters (dd/mm/yyyy). Validity of date provide will not be checked. When the backspace is pressed it will remove the last two character if last character is slash. Otherwise it will remove last character from the input field. The input will not accept characters other than numbers (0 to 9). Let's jump into the code. We will use bootstrap for awesome look: HTML Code: <div class="container" ng-app="myApp" ng-controller="myAppCtrl"> <div class="row"> <div class="col-sm-8 col-sm-offset-2"> <form class="form-horizontal"> <h4 class="bg-primary">Auto Slashing Date using Angularjs Directive</h4> <div class=...

Let me ask you one question. Can a veiwValue and modelValue have same value into a different format? The answer is YES . Here we will see how it can be possible. We will see it through a simple example that converts date string (viewValue) into timestamp (modelValue). We will use a text box to enter a date string (dd/mm/yyyy) and convert it into timestamp that will be stored into model value. The trick is that we will use $parsers to convert the date string into the timestamp and $formatters to change the timestamp stored in modelValue to date string that will be shown on text input. Let's see the codes first: HTML Code: <h4>Date to Timestamp</h4> <div class="form-group"> <label for="date1" class="col-sm-3 control-label">Date1 VeiwValue:</label> <div class="col-sm-3"> <input type="text" id="date1" class="form-control" name="date1" ng-model="ob...

$parsers and $formatters are array of function defined on ngModelController . When there is change in values (view or model), the value is passed through the $parsers or $formatters pipeline to convert it according to the needs. $parsers (View to Model): $parsers is an array of function which executes when there is change in view  value ( $veiwValue ), usually via user input. $parsers cause the conversion of view value into the form desirable to assign in model value. The value is passed through each $parsers function and the return value of one function is passed to next function. Last return value is passed to $validators and after validation the value is assigned to model. These $parsers functions are called array order (i.e. index 0 to n). $parsers are not called when there is change in model value programmatically. $parsers function must return some value. If it not, causes parse error and model value is set to undefined . Let's see the simple ...

ngIf and ngShow directives are used very frequently in Angular apps. Here will the difference between these two through an example. Firstly, let's see the main difference between these two as in angular docs: ngIf differs from ngShow and ngHide in that ngIf completely removes and recreates the element in the DOM rather then changing its visibility via display css property. The main points are as follows: ngShow directive uses css display property to show and hide the element in DOM. It does't remove the element from the DOM. It just set class="ng-hide" to hide the element and removes the ng-hide class to show the element. ngIf directive remove and reinsert the element based on the expression provided in ng-if directive. The inserted element has the state which was initialized at the time of compilation. If we change any css property of the element or set any class, that css property and class will be lost if the ng-if expression becomes false and...

Angularjs provide an directive for the Date and Number input elements. We may be in a problem while handling the form having these as input from the user. There is always a type miss match between the value provided or accepted by these input and and the value accepted by the MySQL database. In Angular, we send and receive data in a JSON format to prevent the page reload. JSON are provided into a string form, we need to process the JSON string at client side. Date , Integer and Float values are provided into string format so, we need to process the these values. To show how to tackle this type mismatch, I have created an simple app that take one text, one float, one integer and one date value from the user and send it to server for storing into the database and return the inserted data item back to the user into JSON format. Before going into the app, it should be noted that. HTML5 date input takes and provide Date object HTML5 number input takes number ...