Syntax:
if (condition)
{
        //True-block;
}
else
{
        //False-block;
}

The if ... else statement is a conditional statement in PHP. It executes one block of code if a condition is true and another block of code if the condition is false.

There are several types of conditional statements in PHP. They are
1. 'if' statement
2. 'if...else' statement
3. 'if...elseif...else' statement
4. 'switch' statement

< ?php
＄x = "August";
if (＄x == "January'') {
echo "Happy Republic Day";
}
elseif (＄x == "August'') {
echo "Happy Independence Day!!!";
}
else{
echo "Nothing to show";
}
? >

(i) The switch-case statement is an alternative to if... elseif... else statement which does almost the same thing.
(ii) The switch-case statement tests a variable against a series of values until it finds a match, and then executes the block of code corresponding to that match.
(iii) The switch statement executes line by line, unlike if... elseif...else.
(iv) It also executes all the subsequent case statement till the end of the switch block automatically.
(v) To prevent this add a break statement to the end of each case block.

(i) Conditional statements are useful for writing decision making logics. It is the most important feature of many programming languages, including PHP.
(ii) When we write the code for conditional statements very often, we can perform different actions for different decisions in different business logic.

Conditional statements in PHP are implemented by the following types:
(i) if Statement
(ii) if... else Statement
(iii) if... elseif... else Statement
(iv) switch Statement
(i) If statement in PHP:
If statement executes a statement or a group of statements if a specific condition is satisfied as per the
user expectation.
Syntax:
if (condition)
{
Execute statement(s) if condition is true;
}
(ii) If else statement in PHP:
If statement executes a statement or a group of statements, if a specific condition is satisfied by the user
expectation. When the condition gets false (fail) the else block is executed.
Syntax:
if (condition)
{
Execute statement(s) if condition is true;
}
else
{
Execute statement(s) if condition is false;
(iii) If elseif else statement
It is a combination of if-else statement. More than one statement can execute the condition based on user needs.
Syntax:
if (1st condition)
{
Execute statement(s) if condition is true;
}
elseif (2nd condition)
{
Execute statement(s) if 2nd condition is true;
}
else
{
Execute statement(s) if both conditions are false;
}
(iv) Switch Statement
It is used to perform different actions based on different conditions.
Syntax:
switch (n) {
case label 1:
code to be executed if n-label1;
break;
case label2:
code to be executed if n=label2;
break;
***
default:
code to be executed if n is different from all labels;
}

(i) If statement in PHP: If statement executes a statement or a group of statements if a specific condition is satisfied as per the users expectation. This is the simplest PHP's conditional statement and can be written in the following form.
Syntax:
if (condition)
{
     // code to be executed if condition is true;
}
(ii) If else statement in PHP: The if statement evaluates a condition and executes a set of code if the condition is true and another set of code if the condition is false.
Syntax:
if(condition)
{
       //True-block;
}
else
{
       //False-block;
}
(iii) If-elseif-else statement in PHP: If-elseif-else statement is a combination of if-else statement. Here multiple conditions can be checked and action is based on the result of the condition.
Syntax:
if (Condition 1)
{
          //code to be executed if condition 1 is true;
}
elseif (condition2)
{
         //code to be executed if condition1 is false and condition2 is true;
}
elseif (condition3)
{
         // code to be executed if condition1 and condition2 are false and condition3 is true;
}
else
{
         //code to be executed if all conditions are false;
}
Switch case: The switch case is an alternative to the if.. elseif.. else statement which executes a block of code corresponding to the match.
Syntax:
switch (expression)
case value1:
           //code to be executed if expression= value1; break;
case value2;
           //code to beexecuted if expression = value2; break;
...
default:
           //code to be executed if cexpression is not equal to any of the values;
}