JavaScript capitalizes the first letter of the word, the remaining lowercase

//1 People wrote it, and I took it for reference.functiontitlecase (str) {varArray = Str.tolowercase (). Split ("");  for(vari = 0; i < Array.Length; i++) {Array[i]= Array[i][0].touppercase () + array[i].substring (1, array[i].length); }  varString = Array.join (""); returnstring;} Titlecase ("I ' m a Little tea pot");//2 wrote it myself.functiontitlecase (str) {vararr = Str.tolowercase (). Split (');    Console.log (arr);  for(vari = 0; i < arr.length; i++) {Arr[i]= Arr[i].replace (arr[i][0], arr[i][0].touppercase ()); }    varstring = Arr.join (' ');    Console.log (string); returnstring;} Titlecase ("Short and SToUt");

There are many mistakes in the process. Originally wanted to record, but found nothing good to write, even.

You are welcome to indicate errors, provide advice ...

JavaScript capitalizes the first letter of the word, the remaining lowercase