How to correctly use loop - imacros

Question

I have macros that invites friends to FB groups, friends name is taken from CSV file, so i need write loop, than will invites all people from csv file . Here is my macros
var macro,start;
macro = "CODE:";
macro += "SET !ERRORIGNORE YES" + "\n";
macro += "SET !EXTRACT_TEST_POPUP NO" + "\n";
macro += "SET !DATASOURCE FB<SP>Groups.csv" + "\n";
macro += "SET !DATASOURCE_COLUMNS 1000" + "\n";
macro += "SET !LOOP 1" + "\n";
macro += "SET !DATASOURCE_LINE {{!LOOP}}" + "\n";
macro += "URL GOTO=" + "\n";
macro += "TAG POS=1 TYPE=I ATTR=CLASS:" + "\n";
So i think from here must starts loop
macro += "TAG POS=2 TYPE=SPAN ATTR=TXT:Invite<SP>Friends" + "\n";
macro += "SET !DATASOURCE FB<SP>Users.csv" + "\n";
macro += "SET !DATASOURCE_COLUMNS 1000" + "\n";
macro += "SET !LOOP 1" + "\n";
macro += "SET !DATASOURCE_LINE {{!LOOP}}" + "\n";
macro += "TAG POS=1 TYPE=INPUT:TEXT ATTR=CLASS:" + "\n";
macro += "TAG POS=1 TYPE=SPAN ATTR=CLASS:uiButtonText" + "\n";
iimPlay(macro)

Answer 1

Play with this snippet:
var macro = "CODE:";
for (i = 1; i <= 3; i++) {
macro += "SET !DATASOURCE FB<SP>Users.csv" + "\n";
macro += "SET !DATASOURCE_LINE " + i + "\n";
macro += "PROMPT {{!COL1}}" + "\n";
iimPlay(macro);
}
Hope, you can catch the idea.
Here is a way of how to define the number of rows in your csv-file:
var numRows = 0;
while (true) {
var macro = "SET !DATASOURCE FB<SP>Users.csv" + "\n";
macro += "SET !DATASOURCE_LINE " + (numRows + 1) + "\n";
if (iimPlayCode(macro) == 1)
numRows++;
else
break;
}
alert(numRows);