Transcript Internet Forms and Database

Internet Forms and Database
Bob Kisel
Amgraf, Inc.
[email protected]
Internet Forms and Database

Types of Databases Available for Internet
Forms
 The Basics of Iform Database Creation
 The Basics of Iform Database Interaction
Types of Databases Available

MySQL Open Source Database (either
Unix or Win32 versions)
 Oracle (Unix or Win32 also)
 SQL Server 2000
 Access 2000 (Possible but I would not
recommend it.)
Access Methods

We provide and recommend Perl DBI
CGI scripting to interface to the database
manager used.
 Native interface code can written that is
invoked by the script interface.
Database Operations

Submit Form Data to Database
 Load Reference Data Into Select Boxes
 Load Previous Form Data
 Load One or More Fields Based on Data
Input
 Save Form Data Without Doing Submit
Submit Form Data

All Non-Disabled Input Fields are passed
to the CGI script. (Be careful of fields
disabled based on other criteria, if they
need to go with submitted data, enable in
beforesubmit function.)
 All Input Fields are Subscripted, make
certain script allows for this.
Load Reference Data

Typically to Load Data into Select Lists
 Setup Criteria
 Invoke _initSelection JavaScript
Function
 Arguments: (Script Path, Criteria,
Display_Mode, Select List Object)
Load Reference Data

Script Path: Relative or Absolute Path to
Server Script on Same Server Where
Page was Served From.
 Typically we Like to Put Them All in a
“Query” Directory Since They May be
Useful to Other HTML Pages and also so
that if one is Similar to Another, we Copy
and Edit it.
Load Reference Data

Criteria is a String of Keyword=Value
Pairs Separated by the “&” Character.
 ALL Values should passed to JavaScript
“escape” function singly if there is any
chance of containing Non-alphanumeric
characters.
Load Reference Data

Server Script Looks for Given Keywords
 Builds the Actual SQL Command
 Formats the Return Data as
 Index=Value
 JavaScript then Loads Data into Select
List in Order Returned.
 Note: Index is a Unique Value for List. It
may be a Number or Key from Database.
Load Reference Data

Display Mode is:
 1 – Leave a blank line at top of Select List
 0 – No Blank Line at Top of List
 -1 – If Only One Line Returned, No
Blank, else Add a Blank Line to Top
Load Previous Form Data

Typically a Server Script is Required to
Dynamically Modify the HTML Data for
the Page.
 This is Done by Inserting Code into the
“initialize” function of the HTML Page.
 This code will set the value of one or
more fields.
Load Previous Form Data

In the case of most forms the values of all
the fields are set in the initialize function.
 In other cases only a Key value is set and
the code in the initialize function then
initializes all of the “dependent” fields
based on this.
 You need to pick the method that works
best for your system design.
Load Dependent Fields

Allows you to load one or more fields
based on a criteria string passed to a
server CGI script.
 The formulation of criteria identical to
loading reference data.
 _InitDependentFields Function
 (Script Path, Criteria, Object Array, Key
Array, Object Count)
Load Dependent Fields

Object Array and Key Array are
sequenced the same.
 Object array is pointers to input fields to
be filled in.
 Key array are strings that are matched to
the script return data keys to identify
which field gets which value.
Load Dependent Fields

This is easy to setup in the JavaScript code, just
difficult to type all the values in without
mistake. (Not bad if only setting up to about 5
fields, bad if it is the entire form.)
 If you setup up your form to use an Input
database, code is generated to load the field
arrays for each table, but you must insert code
to invoke _InitDependentFields function.
Load Dependent Fields

This prevents problems with typing while
allowing you to control precisely when
the server script is called to load the data.
 Typically this is done in initialize function
but may be invoked again if some
selection is made to reflect a new criteria.
 The goal is to load data only when
needed.
Save Form Data

There are cases when you want to be able
to save the data filled in the form without
actually leaving the form.
 Case 1 – The form needs to be saved
multiple times, varying 1 or 2 fields and
you don’t want to go into and out of the
form multiple times.
Save Form Data

Case 2 – You open a sub-form to expand
the technique for data collection, and the
results of the sub-form need to be
captured. Typically when the sub-form is
done, it must close its own window to
return control to original form, not via
the “submit”.
Some of my Favorite Examples

MO State Highway Patrol.
 Bank Form Ordering.