while（var row = fn（））;

Question

Is there any equivalent metod to make like an php mysql_fetch_array while loop in js?

in php you can do:

<?php
while ($row = mysql_fetch_array($result)) {
    echo "my name is " . $row['name'] . " and i'm " . $row['age'] . " yeas old";
}
?>

i have this object/array:

function fetch_array(arr) {
    // My magic fn that dose not work well, b/c it change the orginal refence
    return arr.shift();
}
var result = [{
    name: "Bob",
    age: 12
}, {
    name: "Jim",
    age: 18
}]

// And want to do:


while (row = fetch_array(result)) {
     alert("my name is " + row["name"] + " And I'm " + row['age'] + " years old");
 }

// returns zero :(​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​ dont want that
console.log(result.length);

Answer 1

Array.shift removes the first element of the array, so when you're done looping through it like that, it's empty.

If all you want to do is to go through it and use the data, try this:

var row;
for (var i = 0, l = result.length; i < l; i++) {
    row = result[i];
    alert("my name is " + row["name"] + " And I'm " + row['age'] + " years old");
}

// returns 2
console.log(result.length);

or change the fetch_array function to this, and leave the rest as it is:

var index = 0;
function fetch_array(arr){
   return arr[index++]; 
}

You would have to reset the index variable to 0 if you wanted to loop through it again though.