function validate_required(field,alerttxt)
    {
      
     with (document.getElementById(field))
      {
       
      if (value==null||value=="")
        {
        alert(alerttxt);
        
        return false;
        
        }
        else 
         {
         return true;
         }
      }
   }

function validate_email(field,alerttxt)
  {
   with (document.getElementById(field))
     {
     apos=value.indexOf("@")
     dotpos=value.lastIndexOf(".")
    if (apos<1||dotpos-apos<2) 
       {
         alert(alerttxt);return false;
       }
   else {return true;}
       }
    }

function validate_form()
     {
	  
      
       if (validate_required("txtname","Name must be filled out!")==false)
           {
            
           document.getElementById("txtname").focus();
           
           return false;
            }
       if (validate_required("txtphone","Phone Number must be filled out!")==false)
           {
           document.getElementById("txtphone").focus();
           return false;
           }
           
        
        if (validate_required("txtemail","Email ID must be filled out!")==false)
           {
           document.getElementById("txtemail").focus();
           return false;
           }
        if (validate_email("txtemail","Not a valid e-mail address!")==false)
             {
             document.getElementById("txtemail").focus();
             return false;
             }
        if (validate_required("txtcomment","Content must be filled out!")==false)
           {
           document.getElementById("txtcomment").focus();
           return false
           } 
           
         
  
      
    }