Javascript ReIndex Array keys

Question

What is the fastest Way to reindex an array?

var testArray = new Array();
//before
testArray[343]="qwerty";
testArray[735]="asdfgh";
testArray[1333]="zxcvbn";

//after
testArray[0]="qwerty";
testArray[1]="asdfgh";
testArray[2]="zxcvbn";