html - Clear out an error message instead of appending with javascript -

in html form have warn user has enter level in inputbox, if clicks button again clear off error message , print out again. add more error messages add error message appends end of previous message.

function validateform () {      var msg = ""        , result = true;        if (document.examentry.name.value === "") {          msg = document.createtextnode("you must indicate level");          document.getelementbyid('name-msg').appendchild(msg);          document.getelementbyid('name-msg').style.color="red";      }  }

<form name="examentry" method="post">      <input type="text" id="name" name="name">      <span id="name-msg"></span>      <input type="button" name="submit" value="submit" onclick="validateform();">  </form>

here's jsbin

function validateform () {      var result = true;        if (document.examentry.name.value === "") {        document.getelementbyid('name-msg').innerhtml= "you must indicate level";          document.getelementbyid('name-msg').style.color="red";      }  }

<form name="examentry" method="post">      <input type="text" id="name" name="name">      <span id="name-msg"></span>      <input type="button" name="submit" value="submit" onclick="validateform();">  </form>