foreach equivalent of php in jquery?

Question

Is there a foreach code in JQuery as in PHP? I have a code in php,like

<?php foreach ($viewfields as $viewfield): ?>    
if("<?php echo $viewfield['Attribute']['required'];?>"=='true'){
    $("<span class='req'><em> * </em></span>").appendTo("#fb_contentarea_col1down21 #label<?php echo $viewfield['Attribute']['sequence_no']?>");
   }


   if(<?=$viewfield['Attribute']['type'];?>=='text'||<?=$viewfield['Attribute']['type'];?>=='date'||<?=$viewfield['Attribute']['type'];?>=='number'){ 
    $("<input id=input<?=$viewfield['Attribute']['sequence_no'];?> type= 'text' style= 'width:<?=$viewfield['Attribute']['size'];?>px' data-attr=<?=$viewfield['Attribute']['type'];?> ></input><br>").appendTo("#fb_contentarea_col1down21 #<?=$viewfield['Attribute']['sequence_no'];?>");
   }


   else if(<?=$viewfield['Attribute']['type'];?>=='textarea'){
    $("<textarea style= 'width:<?=$viewfield['Attribute']['size'];?>px' data-attr=<?=$viewfield['Attribute']['type'];?> id=input<?=$viewfield['Attribute']['sequence_no'];?>></textarea><br>").appendTo("#fb_contentarea_col1down21 #<?=$viewfield['Attribute']['sequence_no'];?>");
}

Is there any equivalent of foreach in Jquery? How can I accomplish this same functioality in jQuery?

EDIT 1:

I thought it worked but I get an error. The code and the error message is given below.

for(<?=$viewfield;?> in <?=$viewfields;?>){

 if("<?=$viewfield['Attribute']['required'];?>"=='true'){
            $("<span class='req'><em> * </em></span>").appendTo("#fb_contentarea_col1down21 #label<?php echo $viewfield['Attribute']['sequence_no']?>");
 }

 if(<?=$viewfield['Attribute']['type'];?>=='text'||<?=$viewfield['Attribute']['type'];?>=='date'||<?=$viewfield['Attribute']['type'];?>=='number'){ 
            $("<input id=input<?=$viewfield['Attribute']['sequence_no'];?> type= 'text' style= 'width:<?=$viewfield['Attribute']['size'];?>px' data-attr=<?=$viewfield['Attribute']['type'];?> ></input><br>").appendTo("#fb_contentarea_col1down21 #<?=$viewfield['Attribute']['sequence_no'];?>");
 }

 else if(<?=$viewfield['Attribute']['type'];?>=='textarea'){
            $("<textarea style= 'width:<?=$viewfield['Attribute']['size'];?>px' data-attr=<?=$viewfield['Attribute']['type'];?> id=input<?=$viewfield['Attribute']['sequence_no'];?>></textarea><br>").appendTo("#fb_contentarea_col1down21 #<?=$viewfield['Attribute']['sequence_no'];?>");
 }

}

Error message:

syntax error for( in Array)

Can someone help me..

Answer 1

The $.each function is similar.

It allows you to iterate arrays using a callback function where you have access to each item:

var arr = [ "one", "two", "three", "four", "five" ];


$.each(arr, function(index, value) {
  // work with value
});

Maybe is useful to know, if you want to break the loop, you can do it with return false; or if you want to skip only one iteration (continue), you return true;

Answer 2

There is jQuery.each.

Answer 3

If you want to iterate an object, I would recommend the JavaScript variant:

for (var key in obj) {
    alert(key + ': ' + obj[key]);
}

You can also iterate objects in jQuery like this:
Note! Doing this is pretty pointless unless you think this syntax is much simpler to maintain. The below syntax has much more overhead than the above, standard JavaScript, for-loop.

$.each(obj, function (key, value) {
    alert(key + ': ' + value);
});

---

To iterate arrays, this is how you do it in standard JavaScript (assuming arr is the array):

for (var i = 0, l = arr.length; i < l; i++) {
    alert(i + ': ' + arr[i]);
}

To do it in jQuery, you can do it like this:

$.each(arr, function (index, value) {
    alert(index + ': ' + value);
});

Answer 4

Jquery operating on selectors:

$('a').each(function() {
    $(this).click(function(e) {
       e.preventDefault()
       var href = this.href;
       open(href);
    });
    // operate on the anchor node.
});

jQuery direct $.each:

var a = ['one', 'two'];

$.each(a, function() {
    alert(this)
});

JS: Vanilla for loop

 for ( var i = 0, len = 10; i<l; ++i ) {
    alert(i)
 }

JS #2: vanilla for

 var humanLimbs = ['arms', 'legs'];
 for ( var limb in humanLimbs ) {
     if ( humanLimbs.hasOwnProperty(limb) ) {
        alert( limb )
     }
 }

Js #3: infinite loop

for (;;) { alert(1) } // dont try this :p

Answer 5

Javascript supports the for(data in data_array) syntax. jQuery also has a $.each function (as already mentioned)