JavaScript implementation TEXTAREA typewriter effect hint

Very good prompt input content, dynamic hints, give people intimacy

<textarea id= "Content" name= "Content" cols= "5" rows= "style=" width:450px;height:50px "class=" text "onchange=" Checkcontent () "onclick=" Javascript:flush (); ></textarea>
<script language= "javascript" type= "Text/javascript" >
function $ (ID) {return document.getElementById (ID);}
var msgall= "Strive to build excellent programming learning station." "
var msg = "Enter the question content, click" I want to ask questions. " ;
var interval = 100
var spacelen = 100;
var space10= "";
var seq=0;
var cont=true
function Scroll () {
len = msg.length;
$ ("content"). Value = msg.substring (0, seq+1);
seq++;
if (seq >= len) {
seq = 0;
var per=math.round (Math.random () * (5-1)) +1;
Switch (PER) {
Case 1:msg= "Programming introductory network www.bianceng.cn hint information one";
Case 2:msg= "Hint Information 2 introductory network www.bianceng.cn";
Case 3:msg= "Hint Information 3 introductory network www.bianceng.cn";
Case 4:msg= "Hint Information 4 introductory network www.bianceng.cn";
Case 5:msg= "Hint Information 5 introductory network www.bianceng.cn";
}
if (cont) {
Window.xywtimeout ("Scroll ();", interval);
}
else{
$ ("content"). value= "";
}
}
Else
if (cont) {
Window.xywtimeout ("Scroll ();", interval);
}
else{
$ ("content"). value= "";
}
}
Scroll ();
function Flush () {
$ ("content"). value= "";
Cont=false;
$ ("content"). Onclick=function () {return void (0);};
}
</script>