Add Working-with-selections

Author: danheberden

content/jquery-fundamentals/jquery-basics/working-with-selections.md

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+---
+chapter : "jqfundamentals"
+section : "3"
+title   : "Working with Selections"
+---
+## Working with Selections
+
+Once you have a selection, you can call methods on the selection. 
+Methods generally come in two different flavors: getters and setters. 
+Getters return a property of the first selected element; setters set a property on all selected elements.
+
+### Chaining
+
+If you call a method on a selection and that method returns a jQuery object, 
+you can continue to call jQuery methods on the object without pausing for a semicolon.
+
+<div class="example" markdown="1">
+Chaining
+
+    $('#content').find('h3').eq(2).html('new text for the third h3!');
+</div>
+
+If you are writing a chain that includes several steps, you (and the person who comes after you) may find your code more readable if you break the chain over several lines.
+
+<div class="example" markdown="1">
+Formatting chained code
+
+    $('#content')
+    	.find('h3')
+    	.eq(2)
+    	.html('new text for the third h3!');
+</div>
+
+If you change your selection in the midst of a chain, jQuery provides the $.fn.end method to get you back to your original selection.
+
+<div class="example" markdown="1">
+Restoring your original selection using $.fn.end
+
+    $('#content')
+    	.find('h3')
+    	.eq(2)
+        	.html('new text for the third h3!')
+    	.end() // restores the selection to all h3's in #content
+    	.eq(0)
+        	.html('new text for the first h3!');
+</div>
+
+<div class="note" markdown="1">
+### Note
+
+Chaining is extraordinarily powerful, and it's a feature that many libraries have adapted since it was made popular by jQuery. 
+However, it must be used with care. Extensive chaining can make code extremely difficult to modify or debug. 
+There is no hard-and-fast rule to how long a chain should be — just know that it is easy to get carried away.
+</div>
+
+### Getters & Setters
+
+jQuery “overloads” its methods, so the method used to set a value generally has the same name as the method used to get a value. 
+When a method is used to set a value, it is called a setter. 
+When a method is used to get (or read) a value, it is called a getter. 
+Setters affect all elements in a selection; getters get the requested value only for the first element in the selection.
+
+<div class="example" markdown="1">
+The $.fn.html method used as a setter
+
+    $('h1').html('hello world');
+</div>
+
+<div class="example" markdown="1">
+The html method used as a getter
+
+    $('h1').html();
+</div>
+
+Setters return a jQuery object, allowing you to continue to call jQuery methods on your selection; 
+getters return whatever they were asked to get, meaning you cannot continue to call jQuery methods on the value returned by the getter.