function CountWords (this_field, show_word_count, show_char_count) {

if (show_word_count == null) {
show_word_count = true;
}

if (show_char_count == null) {
show_char_count = false;
}

var char_count = this_field.value.length;
var fullStr = this_field.value + " ";
var initial_whitespace_rExp = /^[^A-Za-z0-9]+/gi;
var left_trimmedStr = fullStr.replace(initial_whitespace_rExp, "");
var non_alphanumerics_rExp = rExp = /[^A-Za-z0-9]+/gi;
var cleanedStr = left_trimmedStr.replace(non_alphanumerics_rExp, " ");
var splitString = cleanedStr.split(" ");
var word_count = splitString.length -1;


if (fullStr.length <2) {
word_count = 0;
}
if (word_count == 1) {
wordOrWords = " word";
}
else {
wordOrWords = " words";
}
if (char_count == 1) {
charOrChars = " character";
} else {
charOrChars = " characters";
}
if (show_word_count & show_char_count) {
alert ("Word Count:\n" + "    " + word_count + wordOrWords + "\n" + "    " + char_count + charOrChars);
}
else {
if (show_word_count) {
alert ("Word Count:  " + word_count + wordOrWords);
}
else {
if (show_char_count) {
alert ("Character Count:  " + char_count + charOrChars);
      }
   }
}
return word_count;
}

<form>
<textarea cols="40" name="x" rows="5"> </textarea>
<input type=button value="Count" OnClick ="CountWords(this.form.x, true, true);">
</form>