JavaScript by Example: JavaScript Core Objects. Pt. 1


Arrayname.push(new elements); // Appended to the array Example: myArray.push("red", "green", "yellow");

Arrayname.push(new elements); // Appended to the array

Example:

myArray.push("red", "green", "yellow");


<html> <head><title>Array push() method</title> </head> <body> <script language="JavaScript"> 1 var names=new Array("Tom", "Dan", "Liz", "Jody"); 2 document.write("<b>Original array: "+ names + "<br>"); 3 names.push("Daniel","Christian"); 4 document.write("New array: "+ names + "</b>"); </script> </body> </html>

<html>

<head><title>Array push() method</title>

</head>

<body>

1 var names=new Array("Tom", "Dan", "Liz", "Jody");

2 document.write("<b>Original array: "+ names + "<br>");

3 names.push("Daniel","Christian");

4 document.write("New array: "+ names + "</b>");

</script>

</body>

</html>


An Array object called names is declared and intialized.
The contents of the array (i.e., all of its elements) are displayed. The push() method appends two new elements, "Daniel" and "Christian", to the end of the names array . The array has grown. It is displayed in the browser window with its new elements. (See Figure 9.8.)

An Array object called names is declared and intialized.

The contents of the array (i.e., all of its elements) are displayed.
The push() method appends two new elements, "Daniel" and "Christian", to the end of the names array
.
The array has grown. It is displayed in the browser window with its new elements. (See Figure 9.8.)


var return_value=Arrayname.shift(); Arrayname.shift( new elements); // Prepended to the array Example: var shifted_off = myArray.shift(); myArray.shift("blue","yellow");

var return_value=Arrayname.shift();

Arrayname.shift( new elements); // Prepended to the array

Example:

var shifted_off = myArray.shift();

myArray.shift("blue","yellow");


<html> <head><title>Array shift() and unshift() methods</title> </head> <body> <script language="JavaScript"> 1 var names=new Array("Dan", "Liz", "Jody" ); document.write("<b>Original array: "+ names + "<br>"); 2 names.shift(); document.write("New array after the shift: " + names); 3 names.unshift("Nicky","Lucy"); // Add new elements to the beginning of the array document.write("<br>New array after the unshift: " + names); </script> </body> </html>

<html>

<head><title>Array shift() and unshift() methods</title>

</head>

<body>

1 var names=new Array("Dan", "Liz", "Jody" );

document.write("<b>Original array: "+ names + "<br>");

2 names.shift();

document.write("New array after the shift: " + names);

3 names.unshift("Nicky","Lucy");
// Add new elements to the beginning of the array

document.write("<br>New array after the unshift: " + names);

</script>

</body>

</html>


A new Array object called names is created.
The first element of the array is shifted off, shortening the array by 1. The unshift() method will prepend to the beginning of the array, the names "Nicky" and "Lucy", thereby making it longer by two elements. (See Figure 9.9.)

A new Array object called names is created.

The first element of the array is shifted off, shortening the array by 1.
The unshift() method will prepend to the beginning of the array, the names "Nicky" and "Lucy", thereby making it longer by two elements. (See Figure 9.9.)


<html> <head><title>Array slice() method</title> </head> <body> <script language="JavaScript"> 1 var names=new Array("Dan", "Liz", "Jody", "Christian", "William"); document.write("<b>Original array: "+ names + "<br>"); 2 var sliceArray=names.slice(2, 4); document.write("New array after the slice: "); 3 document.write(sliceArray); </script> </body> </html>

<html>

<head><title>Array slice() method</title>

</head>

<body>

1 var names=new Array("Dan", "Liz", "Jody", "Christian",

"William");

document.write("<b>Original array: "+ names + "<br>");

2 var sliceArray=names.slice(2, 4);

document.write("New array after the slice: ");

3 document.write(sliceArray);

</script>

</body>

</html>


This is the original array of names.
The slice() method will start at position 2, copy Jody into the new array, then Christian, and stop just before position 4, William. The original array is not affected by the slice. The new array created by the slice() method is displayed. (See Figure 9.10.)

This is the original array of names.

The slice() method will start at position 2, copy Jody into the new array, then Christian, and stop just before position 4, William. The original array is not affected by the slice.
The new array created by the slice() method is displayed. (See Figure 9.10.)


Arrayname.splice( index position, number of elements to remove); Arrayname.splice(index position, number of elements to remove, replacement elements); Example: myArray.splice( 3, 2); myArray.splice( 3, 2, "apples","oranges");

Arrayname.splice( index position, number of elements to remove);

Arrayname.splice(index position, number of elements to remove,

replacement elements);

Example:

myArray.splice( 3, 2);

myArray.splice( 3, 2, "apples","oranges");


<html> <head><title>Array splice() method</title> </head> <body> <script language="JavaScript"> // splice(starting_pos, number_to_delete, new_values) 1 var names=new Array("Tom","Dan", "Liz", "Jody"); document.write("<b>Original array: "+ names + "<br>"); 2 names.splice(1, 2, "Peter","Paul","Mary"); 3 document.write("New array: "+ names + "</b>"); </script> </body> </html>

<html>

<head><title>Array splice() method</title>

</head>

<body>

// splice(starting_pos, number_to_delete, new_values)

1 var names=new Array("Tom","Dan", "Liz", "Jody");

document.write("<b>Original array: "+ names + "<br>");

2 names.splice(1, 2, "Peter","Paul","Mary");

3 document.write("New array: "+ names + "</b>");

</script>

</body>

</html>


An Array object called names is declared and intialized.
The splice() method allows you to delete elements from an array and optionally replace the deleted elements with new values. The first arguments to the splice method are 1, 2. This means: start at element 1, and remove a length of 2 elements. In this example, element 1 starts with "Dan" (element 0 is "Tom"). "Liz" is the second element. Both "Dan" and "Liz" are removed. The next three arguments, "Peter", "Paul", and "Mary", are then inserted into the array, replacing "Dan" and "Liz". The new names array is displayed in the browser window. (See Figure 9.11.)

An Array object called names is declared and intialized.

The splice() method allows you to delete elements from an array and optionally replace the deleted elements with new values. The first arguments to the splice method are 1, 2. This means: start at element 1, and remove a length of 2 elements. In this example, element 1 starts with "Dan" (element 0 is "Tom"). "Liz" is the second element. Both "Dan" and "Liz" are removed. The next three arguments, "Peter", "Paul", and "Mary", are then inserted into the array, replacing "Dan" and "Liz".
The new names array is displayed in the browser window. (See Figure 9.11.)