Php tutorial 1.2

Basics of PHP

1) Variables:

Variables are used for storing values, like text strings, numbers or arrays.
When a variable is declared, it can be used over and over again in your script.
All variables in PHP start with a $ sign symbol.
The correct way of declaring a variable in PHP: $var_name = value;

2) String Variables:

String variables are used for values that contain characters.
After we create a string we can manipulate it. A string can be used directly in a function or it can be stored in a variable.
Below, the PHP script assigns the text "Hello World" to a string variable called $txt:
<?php
$txt="Hello World";
echo $txt;
?>

3)Operators: Operators are used to operate on values.

1. Arithmetic Operator:

Arithmetic operators are used to perform simple mathematical operators.
Example:
• Addition (+)
• Subtraction (-)
• Multiplication (*)
• Division (/)
• Modulus (%)

2. Assignment Operator:

Assignment operators are used to set a variable equal to a value or set a variable to another variable's value. Such an assignment of value is done with the "=", or equal character.
Example:
• $my_var = 4;
• $another_var = $my_var;
Now both $my_var and $another_var contain the value 4. Assignments can also be used in conjunction with arithmetic operators.

3. Comparison Operator:

Comparisons are used to check the relationship between variables and/or values.Comparison operators are used inside conditional statements and evaluate to either true or false.Here are the most important comparison operators of PHP.
Assume: $x = 4 and $y = 5;

4. Logical Operator:

The logical operators compare Boolean expressions and return a Boolean result.

Examples:

1) concat.php (concat two String)

<?php
//Double lines indicates that it is a comment
/* Indicates multiline Comment*/
$str1="This is Programmingkatta Blog";
$str2="written to gain Knowledge";
$str3=$str1." ".$str2;
echo"$str3";
//The above code will give First Line of Output

//-----------------------2nd line output------------------------
echo "<br />";//<br />-Use to break a line
$aray=array();//array()-fuction to declare it as array.
$aray[0]="Makarand";
echo $aray[0];
//--------------------------------------------------------------
echo "<br />";
$name="Aishwarya";
echo "1. My name is ".$name;//3rd line output
echo "<br />";
echo "2. My name is ".$aray[0];//4th line output
echo "<br />";
echo "3. My name is $name";//5th line output
//--------------------------------------------------------------
echo "<br />";
echo "<input type=\"text\" id=\"name\" value=\"$name\" />";
echo "<br />";
echo "<input type=\"text\" id=\"name2\" value=\"".$aray[0]."\">";
echo "<br />";
echo "This is example of split string";

?>

//===============================================================

2) maths.php (Simple mathematical operations using PHP)

<?php
$x=30;
$y=20;
$a=$x+$y;
$b=$x-$y;
$c=$x*$y;
$d=$x/$y;
$e=$x%$y;
echo"x=$x<br />";
echo"y=$y<br />";
echo"x+y=$a<br />";//add
echo"x-y=$b<br />";//sub
echo"x*y=$c<br />";//mul
echo"x/y=$d<br />";//div
echo"x%y=$e<br />";//modulus
?>

//===============================================================

3)Display array data using table

<?php
echo"<h1>Records:</h1>";

$firstname=array();
$firstname[0]="Makarand";
$firstname[1]="Bhumika";
$firstname[2]="Shweta";
$firstname[3]="Athul";
$firstname[4]="Ketan";

$lastname=array();
$lastname[0]="Dalal";
$lastname[1]="Dhotre";
$lastname[2]="Gupta";
$lastname[3]="Pavithran";
$lastname[4]="Kasar";

$mobilenumber=array();
$mobilenumber[0]=6785234265;
$mobilenumber[1]=5893214785;
$mobilenumber[2]=1423879654;
$mobilenumber[3]=7851236549;
$mobilenumber[4]=4582316578;

$email=array();
$email[0]="vishakha@gmail.com";
$email[1]="charvi@gmail.com";
$email[2]="rucha@gmail.com";
$email[3]="radhika@gmail.com";
$email[4]="riddhi@gmail.com";

$city=array();
$city[0]="Mumbai";
$city[1]="Delhi";
$city[2]="Kolkata";
$city[3]="Pune";
$city[4]="Banglore";

//To create table and call values in table Below code is used
echo "<table border=\"8\">
<tr>
<th>First Name</th>
<th>Last Name</th>
<th>Mobile Number</th>
<th>Email</th>
<th>City</th>
</tr>
<tr><td>$firstname[0]</td>
<td>$lastname[0]</td>
<td>$mobilenumber[0]</td>
<td>$email[0]</td>
<td>$city[0]</td></tr>
<tr><td>$firstname[1]</td>
<td>$lastname[1]</td>
<td>$mobilenumber[1]</td>
<td>$email[1]</td>
<td>$city[1]</td></tr>
<tr><td>$firstname[2]</td>
<td>$lastname[2]</td>
<td>$mobilenumber[2]</td>
<td>$email[2]</td>
<td>$city[2]</td></tr>
<tr><td>$firstname[3]</td>
<td>$lastname[3]</td>
<td>$mobilenumber[3]</td>
<td>$email[3]</td>
<td>$city[3]</td></tr>
<tr><td>$firstname[4]</td>
<td>$lastname[4]</td>
<td>$mobilenumber[4]</td>
<td>$email[4]</td>
<td>$city[4]</td></tr>
</table>";
?>

Related Post:

1.Loops,Conditional Statements
2.Important String Functions