Pomoc script

function validate()
  {
    var i = 0;
    var invalid = new Array(2);
    invalid[0] = "\\";
    invalid[1] = "/";
    invalid[2] = ":";
    invalid[3] = "*";
    invalid[4] = "?";
    invalid[5] = "<";
    invalid[6] = ">";

    if( document.file_information.file_name.value == "" ){
      alert("You have not entered a filename!");
      return false;
    }
    else if( document.file_information.file_name.value.indexOf(' ') == 0 ) {
      alert("First letter can't be a space!");
      return false;
    }
    else

      while( i < 7 ) {
        if (document.file_information.file_name.value.indexOf(invalid[i]) > -1) {
          alert("Sorry, \ / : \" * ?  < > and spaces are not allowed.");
          return false;
        }
        i++;
      }
    return 1;
  }

<form enctype="multipart/form-data" action="nahraj.php" id="form" method="post" onsubmit="a=document.getElementById('form').style;a.display='none';b=document.getElementById('status').style;b.display='inline';" style="display: inline;">
---blalalalalalala---
</form>

onsubmit="validate()"

function checkform ( form ) {
  if (form.upload.value == "") {
    alert( "Zadajte prosím nejaký súbor pre upload." );
    form.upload.focus();
    return false ;
  }
  return true ;
}

<form enctype="multipart/form-data" action="nahraj.php" id="form" method="post" onsubmit="a=document.getElementById('form').style;a.display='none';b=document.getElementById('status').style;b.display='inline';" style="display: inline;">   

function submit_form(form)
{
  if (!checkform(form)) return false;
  a=document.getElementById('form').style;
  a.display='none';
  b=document.getElementById('status').style;
  b.display='inline';
  return true;
}

onsubmit="return submit_form(this)"

<script language="javascript" type="text/javascript">
function checkform ( form ) {
  if (form.upload.value == "") {
    alert( "Zadajte prosím nejaký súbor pre upload." );
    form.upload.focus();
    return false ;
  }
  return true ;
}
function submit_form(form)
{
  if (!checkform(form)) return false;
  a=document.getElementById('form').style;
  a.display='none';
  b=document.getElementById('status').style;
  b.display='inline';
  return true;
}
</script>