3. 2. 1. Conditionals |
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The format of a simple if statement looks like the following: |
if (expression)
statement;
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If the 'expression' in parentheses evaluates to true, the statement is executed; otherwise, the statement is skipped. |
If two or more lines of code are to be executed, curly braces {} must be used to designate what code belongs in the if statement. |
The keyword else extends the functionality of the basic if statement by providing other alternatives. |
The format of an if...else combination looks like the following: |
if (expression)
statement1;
else
statement2;
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if the expression evaluates to true, statement1 is executed, otherwise, statement2 is executed. |
<html>
<SCRIPT LANGUAGE='JavaScript'>
<!--
var varA = 2;
var varB = 5;
if (varA == 0)
document.write("varA == 0");
else {
if ((varA * 2) >= varB)
document.write("(varA * 2) >= varB");
else
document.write("(varA * 2) < varB");
document.write(varB);
}
//-->
</SCRIPT>
</html>
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