JavaScript寻找最长的单词算法

function findLongestWord(str) {
var myArray = new Array();
for(var i=0;i<str.length;i++){
var myArray= str.split(" ",i);
}

var max=0,second_max=0;
for(var i=0;i<myArray.length;i++){
if(myArray[i].length>max){
second_max = max;
max=myArray[i].length;
}else if(myArray[i]>second_max){
second_max = myArray[i].length;
}
}

return max;
//return str.length;
}

findLongestWord("The quick brown fox jumped over the lazy dog");