Javascript - 在FOR LOOP中以特定间隔执行某些操作

I got a problem while developing javascript based idea..

Here's the main code,

 $.post("datainlines.php", function(data) { 

        var lines = data.split("
");

           for (var i = 1; i < lines.length; i++) {

             sitename= lines[i]; sitetype=lines[i++]; 

             if(i/2 == '0'){ alert current values in sitename and sitetype variables}

            }

       } );

This will get data in datainlines.php via POST, datainlines.php file data structure is like this -

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How to get site name and type in groups, like

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is there anyway to group out and alert per every two loops in for loop ?

Increment your loop value by two:

$.post("datainlines.php", function(data) {

    var lines = data.split("
");

    for (var i = 1; i < lines.length; i+=2) {
        sitename = lines[i];
        sitetype = lines[i+1];
        alert(sitename + " " + sitetype);
    }
});​

Note the i+=2 in the for loop. This will skip every other entry in the array.

As an aside, I think with this line:

if(i/2 == '0')

What you were actually looking for is the modulus:

if(i % 2 === 0)