javascript将多维数组转为一维数组

function flat(arr,result){
    if(!Object.prototype.toString.call(arr) == ‘[object Array]‘){
        return arr;
    }
    result=result||[];
    for(var i=0;i<arr.length;i++){
        if(Object.prototype.toString.call(arr[i]) == ‘[object Array]‘){
            result=flat(arr[i],result);
        }else{
            result.push(arr[i]);
        }
    }
    return result
}

function flat(arr){
    var result=[];
    function flatFn(arr1){
        for(var i=0;i<arr1.length;i++){
            if(!Object.prototype.toString.call(arr1[i]) == ‘[object Array]‘){
                flatFn(arr1[i]);
            }else{
                result.push(arr1[i]);
            }
        }
    }
    flatFn(arr);
    return result;
}