Question

Trying to set a flag in the post to allow processing or not. The javascript isn’t working for me I want to have a dialog box pop up and then set a hidden post bool 0 for canceled and 1 for ok. Is there a better way to set a post value based on the confirm return? Everything I search for brings up ASP.NET and it’s postBack value.

The form is generated using simple JSP (I know it’s outdated and JSTL is better this suites my needs):

<form name="delPlayers" method="post" action="deletePlayer.jsp" class="col6 leftpad3 rightpad3">
   <input type="hidden" name="confirmed" value="0" />
   <select name="playerName">
   <% while (results.next())
      {
         out.print("<option value=\"");
         out.print(results.getString("username"));
         out.print("\">");
         out.print(results.getString("username"));
         out.print("</option>");
      } %>
   </select>
   <input type="submit" name="Submit" class="button" value="Submit" onSubmit="return confirmSubmit()" />
</form>

How I was trying to check the confirm return and set the value before the post.

<script type="text/javascript">
<!--
   function confirmSubmit()
   {
      var r = confirm("Remove " + document.forms['delPlayers']["playerName"].value + "?");
      if (r)
         document.forms['delPlayers']["confirmed"].value = r;
         return true ;
      else
         return false ;
   }
-->
</script>

Answer 1

This part :

 onSubmit="return confirmSubmit()"

should appear inside the <form> tag, not the <input submit> tag. Like this :

<form onSubmit="return confirmSubmit()" name="delPlayers" method="post" action="deletePlayer.jsp" class="col6 leftpad3 rightpad3">

---

[EDIT]

You didn’t get it working cause your javascript structure is not as good as needed. I tried to change your code into something like this, and things seem to be better:

if (r){
    document.forms['delPlayers']["confirmed"].value = r;
    return true ;
}else{
    return false ;
}

Just remember to always use the curly brackets { and } when you write if command inside javascript. You’re not obliged to use them, but it’s a god habit to avoid such nonsensical problem like this.

Technical note : In JS, the if(condition) without curly brakets {} works with only 1 line of command right after it . In your case, there were 2 command, so the “else” statment was illegal. That’s the reason why you alway should use if with curly brackets

if (condition)
      foo()
else
      bar()

is OK. But

if (condition)
      foo()
      any_extra_command();
else
      bar()

will cause an error. So the best for all case was :

if (condition){
      foo();
      any_extra_command();
      ......
      anything_you_want_else();
}else{
      bar()
}