The map method will call the provided function for each value of the array and it will return an array containing the results of those function calls.
The callback function is called with three arguments: the value, the index, and a pointer to the array being used respectively.
In the following example each element of the array is tested to see if it is numeric, if it is, it's passed into the new array, otherwise a zero is inserted.
for ex,
var isNumeric = function(x) {
// returns true if x is numeric and false if it is not.
var RegExp = /^(-)?(\d*)(\.?)(\d*)$/;
return String(x).match(RegExp);
}
var testElement = function(x) {
if (isNumeric(x)) {
return x;
} else {
return 0;
}
}
var myArray = [1,'two',3,'four',5,'six',7,'eight',9,'ten'];
var newArray= myArray.map(testElement);
document.writeln(newArray); // outputs: 1,0,3,0,5,0,7,0,9,0
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