Flow Control...
The control statements contain a block of statements enclosed in curly braces { }.
if Statement:
if ( expression ) {
statements // do these if expression is true
}
if ( expression ) {
statements // do these if expression is true
} else {
statements // do these if expression is false
}
if ( expression1 ) {
statements // do these if expression1 is true
} else if ( expression2 ) {
statements // do these if expression2 is true
} else if ( expression3 ) {
statements // do these if expression3 is true
. . .
} else {
statements // do these no expression was true
}
switch Statement:
The switch statement chooses statements to execute depending on an integer value. The same effect can be achieved with a series of cascading if statements, but in some cases the switch statement is easier to read, and in some compilers it can produce more efficient code. The break statement exits from the switch statement. If there is no break at the end of a case, execution continues in the next case, but this is almost always an error.
switch (expr) {
case c1:
statements // do these if expr == c1
break;
case c2:
statements // do these if expr == c2
break;
case c2: // Multiple values can share same code.
case c3:
case c4:
statements // do these if expr == any of c2, c3, or c4.
break;
. . .
default:
statements // do these if expr != any above
}
while Statement:
The while statement tests an expression. If the expression evaluates to true, it executes the body of the while. If it is false, execution continues with the statement after the while body. Each time after the body is executed, execution starts with the test again. This continues until the expression is false or some other statement (break or return) stops the loop.
while ( testExpression ) {
statements
}
for Statement:
Many loop have an initialization before the loop, and some "increment" before the next loop. The for loop is the standard way of combining these parts.
for ( initialStmt; testExpr; incrementStmt ) {
statements
}
This is the same as:
initialStmt;
while ( testExpr ) {
statements
incrementStmt
}
do Statement:
This is the least used of the loop statements, but sometimes you want a loop that executes one time before testing.
do {
statements
} while ( testExpression );
if Statement:
if ( expression ) {
statements // do these if expression is true
}
if ( expression ) {
statements // do these if expression is true
} else {
statements // do these if expression is false
}
if ( expression1 ) {
statements // do these if expression1 is true
} else if ( expression2 ) {
statements // do these if expression2 is true
} else if ( expression3 ) {
statements // do these if expression3 is true
. . .
} else {
statements // do these no expression was true
}
switch Statement:
The switch statement chooses statements to execute depending on an integer value. The same effect can be achieved with a series of cascading if statements, but in some cases the switch statement is easier to read, and in some compilers it can produce more efficient code. The break statement exits from the switch statement. If there is no break at the end of a case, execution continues in the next case, but this is almost always an error.
switch (expr) {
case c1:
statements // do these if expr == c1
break;
case c2:
statements // do these if expr == c2
break;
case c2: // Multiple values can share same code.
case c3:
case c4:
statements // do these if expr == any of c2, c3, or c4.
break;
. . .
default:
statements // do these if expr != any above
}
while Statement:
The while statement tests an expression. If the expression evaluates to true, it executes the body of the while. If it is false, execution continues with the statement after the while body. Each time after the body is executed, execution starts with the test again. This continues until the expression is false or some other statement (break or return) stops the loop.
while ( testExpression ) {
statements
}
for Statement:
Many loop have an initialization before the loop, and some "increment" before the next loop. The for loop is the standard way of combining these parts.
for ( initialStmt; testExpr; incrementStmt ) {
statements
}
This is the same as:
initialStmt;
while ( testExpr ) {
statements
incrementStmt
}
do Statement:
This is the least used of the loop statements, but sometimes you want a loop that executes one time before testing.
do {
statements
} while ( testExpression );