javascript - Difference between create a new Array and clear the length

If I have to delete all the items in an array, what's the difference between using new Array and length = 0? In the example, apparently the result looks the same.

function MyCtrl($scope) { 
    
    $scope.arrayData = ["1", "2", "3"];
    
    $scope.newArray1 = function(){

    	$scope.arrayData = new Array();
    }    
    
    $scope.newArray2 = function(){
    	$scope.arrayData = [];
    }
        
    $scope.lengthZero = function(){
    	$scope.arrayData.length = 0;
    }    

            
    $scope.populate = function(){
    	$scope.arrayData.push("1", "2", "3");
    }    
 }
 
 

Data:

   

        
{{data}}
    
 
    
    
    
    
    

Answer

There is quite a big difference between just using [] and .length = 0.

If you use = [] you will assign a new reference to the variable, losing your reference to the original. By using .length = 0 you will clear the original array, leaving the original reference intact.