Discusses the concept of branching in web programming languages
Selection Statements#
Most programming languages contain selection statements. Basically, a selection statement is a mechanism that explains whether a statement will be executed or not, depending on a formulated condition. In the PHP programming language, selection statements are applied using the IF and Switch Case statements.
1. IF Statement#
a. Single IF#
The IF statement is an important statement that is definitely present in all programming languages. This statement is useful for creating branches based on certain conditions that must be met.
The general form of the IF Statement is as follows :
if (kondisi) {
statement;
}
else {
statement;
}The working principle is that the command above will be executed if the condition is TRUE or correct, whereas if the condition is wrong / FALSE then the statement above will not be executed.
b. IF and Else Statements#
The ELSE statement is a part of the if statement. Else is used to provide an alternative command if the condition is wrong / FALSE.
General form :
if (kondisi) {
statement_1;
}
else {
statement_2;
}Example: contohpercabanganifelse.php
<html>
<head>
<title> Contoh IF ELSE</title>
</head>
<?php
$nilai = 40;
if ($nilai >= 60) {
echo "Nilai Anda = $nilai. Selamat, Anda Lulus";
} else {
echo "Nilai Anda = $nilai. Sorry, Anda Tidak Lulus";
}
?>
</body>
</html>
Result:
c. Compound IF Statements#
If the else statement provides a second alternative choice, then the ElseIf statement can be used to formulate multiple alternative choices (more than two choices).
General form :
if ( kondisi_1 )
{
Statement_1;
}
elseif ( kondis_2)
{
Statement_2;
}
elseif ( kondisi_3)
{
Statement_3;
}
else
{
Statement_n;
}Example : contohpercabanganifmajemuk.php
<html>
<head>
<title> Contoh IF Majemuk</title>
</head>
<?php
$nilai = 90;
if (($nilai >= 0)&&($nilai < 50))
{ $grade ="E";}
elseif(($nilai >= 50)&&($nilai < 60))
{ $grade ="D";}
elseif(($nilai >= 60)&&($nilai < 75))
{ $grade ="C";}
elseif(($nilai >= 75)&&($nilai < 85))
{ $grade ="B";}
elseif(($nilai >= 85)&&($nilai < 100))
{ $grade ="A";}
else
{ $grade = "Nilai anda di luar jangkauan"; }
echo "Nilai Anda : $nilai, dikonversi menjadi $grade";
?>
</body>
</html>
Result:
Switch Statement#
The next program flow control statement is switch. One of the advantages of switch is that you can immediately evaluate one statement and command actions in larger numbers.
General form :
Switch ( nilai_ekspresi ){
Case nilai_1 : statement_1; break;
Case nilai_2 : statement_2; brea;
Default: statement_n;}Example:
<?php
$angka = 6;
switch ($angka){
case 0: $terbilang = "NOL"; break;
case 1: $terbilang = "SATU"; break;
case 2: $terbilang = "DUA"; break;
case 3: $terbilang = "TIGA"; break;
case 4: $terbilang = "EMPAT"; break;
case 5: $terbilang = "LIMA"; break;
case 6: $terbilang = "ENAM"; break;
case 7: $terbilang = "TUJUH"; break;
case 8: $terbilang = "DELAPAN"; break;
case 9: $terbilang = "SEMBILAN"; break;
default: $terbilang = "Nilai diluar jangkuan!!";
}
echo "Bentuk terbilang dari angka $angka adalah $terbilang";
?>
Result:
