for - statement of language JavaScript

Description:

Repeats a group of statements a specified number of times.

Syntax:

for (statement1; statement2; statement3)
{
[statements]
[break;]
}

The for statement consists of three parts separated by semicolon:

statement1 - Specifies the initial numeric value of the variable used as cycle counter. For example:

var i=0

statement2 - Logical expression that is evaluated at the beginning of each cycle iteration. If the expression returns true, then the iteration is completed, otherwise the cycle is exited.
It is usually a simpe test whether the cycle counter is within the defined range. For example:

i < 20

statement3 - This statement is executed at the end of each iteration. It is usually an incrementation (or decrementation) of corresponding cycle variable. For example:

i++

Note:

break statement can be used inside a loop to provide an alternate way to exit.

For similar purpose in the VBScript language is used the statement For...Next.

Example1:

A simple cycle example. It dumps texts i=1 and i=2 into the Debug item of the INFO system.

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var iRow;

for (iRow = 0; iRow < 2; iRow++)

{

	// test

	Pm.Debug("iRow = " + iRow);

}

Example2:

You can nest For...Next loops by placing one For...Next loop within another. Give each loop a unique variable name as its counter. The following construction is correct:

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var iRow, iCol, iItem;

for (iRow = 1; iRow < 3; iRow++)

{

	for (iCol = 1; iCol < 3; iCol++)

	{

		for (iItem = 1; iItem < 3; iItem++)

		{

			// test

			Pm.Debug("iRow = " + iRow + ", iCol = " + iCol + ", iItem = " + iItem);

		}

	}

}