Skip to main content

Other Ways of Initializing Arrays in PHP

Other Ways of Initializing Arrays in PHP

We had discussed about Arrays in PHP in the post Arrays and Array Processing in PHP. We learnt how we can simply initialize an array by giving values to different indices or using the ‘array’ construct. Besides those methods there are a few others that you should know, which is the topic of this post.

Creating Sequential Arrays

There are times when you want to store sequence or pattern of values in an array. For that task range() function would prove to be very helpful. Suppose if we want to have an array having ten elements from 1 to 10. We can use the following tedious method:

$ar[0]=1;
$ar[1]=2;
$ar[2]=3;


$ar
[9]=10;

or the range function like:

$ar=range(1,10);

the above line of code creates an arrays same as the one above.

This function can also be use with the optional third argument to set the step between values.

Eg.

$ar=range(1,10,2);
//$ar={1,3,5,7,9}

range() function also works with character, so if you want to have an array with elements ‘a’ to ‘z’, it could be done with the following one line of code:

$ar=range('a','z');

Loading Values into arrays from Files

PHP supports a method that can be very helpful at times. You can use this method to load entire file into an array, where ach line in the file becomes a element in the arrays.

Have a look at the code below:

$ar=file("shout_box.txt");

Now suppose if the file had the following content:

I Like PHP
Second Line
Third Line

Arrays ‘$ar’ would contain:

array(3) { [0]=> string(12"I Like PHP " [1]=> 
string(13"Second Line " [2]=> string(10"Third Line" }

As you can see each line in the file has become an element in the array.

Copying one Array to another

If you have an array whose values you want another array to be initialized with, you can use the ‘=’ operator. The equal to ‘=’ operator can \copy one array to another.

$ar=array('a','c','eleven');
$ar2=$ar;
//$ar2= array(3) { [0]=> string(1) "a" [1]=> 
//string(1) "c" [2]=> string(6) "eleven" }

Previous Articles:

Popular posts from this blog

Fix For Toshiba Satellite "RTC Battery is Low" Error (with Pictures)

RTC Battery is Low Error on a Toshiba Satellite laptop "RTC Battery is Low..." An error message flashing while you try to boot your laptop is enough to panic many people. But worry not! "RTC Battery" stands for Real-Time Clock battery which almost all laptops and PCs have on their motherboard to power the clock and sometimes to also keep the CMOS settings from getting erased while the system is switched off.  It is not uncommon for these batteries to last for years before requiring a replacement as the clock consumes very less power. And contrary to what some people tell you - they are not rechargeable or getting charged while your computer or laptop is running. In this article, we'll learn everything about RTC batteries and how to fix the error on your Toshiba Satellite laptop. What is an RTC Battery? RTC or CMOS batteries are small coin-shaped lithium batteries with a 3-volts output. Most laptops use

The Best Way(s) to Comment out PHP/HTML Code

PHP supports various styles of comments. Please check the following example: <?php // Single line comment code (); # Single line Comment code2 (); /* Multi Line comment code(); The code inside doesn't run */ // /* This doesn NOT start a multi-line comment block /* Multi line comment block The following line still ends the multi-line comment block //*/ The " # " comment style, though, is rarely used. Do note, in the example, that anything (even a multi-block comment /* ) after a " // " or " # " is a comment, and /* */ around any single-line comment overrides it. This information will come in handy when we learn about some neat tricks next. Comment out PHP Code Blocks Check the following code <?php //* Toggle line if ( 1 ) {      // } else {      // } //*/ //* Toggle line if ( 2 ) {      // } else {      // } //*/ Now see how easy it is to toggle a part of PHP code by just removing or adding a single " / " from th

Introduction to Operator Overloading in C++

a1 = a2 + a3; The above operation is valid, as you know if a1, a2 and a3 are instances of in-built Data Types . But what if those are, say objects of a Class ; is the operation valid? Yes, it is, if you overload the ‘+’ Operator in the class, to which a1, a2 and a3 belong. Operator overloading is used to give special meaning to the commonly used operators (such as +, -, * etc.) with respect to a class. By overloading operators, we can control or define how an operator should operate on data with respect to a class. Operators are overloaded in C++ by creating operator functions either as a member or a s a Friend Function of a class. Since creating member operator functions are easier, we’ll be using that method in this article. As I said operator functions are declared using the following general form: ret-type operator#(arg-list); and then defining it as a normal member function. Here, ret-type is commonly the name of the class itself as the ope