PRB: Accessing Data Changes in the OnCellChange Event Procedure (283182)

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Steps to Reproduce Behavior

Open a new empty text file in Microsoft Notepad and save it as oncellchange.htm on your hard drive.

Copy and paste the following code into oncellchange.htm, and then save the changes:

<SCRIPT LANGUAGE=VBScript>

Option Explicit

Function DataChanged()
  Dim EmpDSOXML
  Dim ModifiedField

  EmpDSOXML = "XML : " & vbcrlf & EmpDSO.xml
  MsgBox EmpDSOXML
 
  Set ModifiedField = window.event.recordset(window.event.datafld)
  MsgBox ModifiedField.Name &  " : " & ModifiedField.value
End Function

</SCRIPT>

<html >

<title>Employee Information</title>


<BODY>

<xml id=EmpDSO onCellChange="DataChanged()">
<Employees>
  <Employee><EmpID>E001</EmpID><EmpName>Jack</EmpName></Employee>
</Employees>
</xml>

<INPUT datasrc=#EmpDSO datafld="EmpID" Id="EmpID" Name="EmpId"> <BR>
<INPUT datasrc=#EmpDSO datafld="EmpName" Id="EmpName" Name="EmpName">

</BODY>

</html>

Open oncellchange.htm in Internet Explorer, and note that the values in the EmpID and EmpName fields from the single record in the XML DSO are displayed in the HTML Textbox elements that are bound to it.
Change the value that is displayed in the HTML Textbox element that is bound to the EmpName field, and then tab out of the textbox. This action causes the oncellchange event of the XML DSO to fire and trigger the execution of the DataChanged() VBScript function. The code in the DataChanged function displays the DSO's XML, followed by the name and value of the datafield that was modified. Note that the XML and the modified field's value reflect the original data that was stored in the EmpName element before you modified the value in the HTML Textbox.
Shut down Internet Explorer.
Open a new empty text file in Notepad, and then save it as BeforeAfterUpdate.htm on your hard drive.

Copy and paste the following code in BeforeAfterUpdate.htm, and then save the changes:

<SCRIPT LANGUAGE=vbscript>
Option Explicit

Function BefUpdate()
  
  Dim XMLBefUpdate
  Dim oXMLNode 
  Dim oldValue
  Dim newValue
  Dim output

  XMLBefUpdate = "XML Before Update : " &  vbcrlf & EmpDSO.xml
  MsgBox XMLBefUpdate

  oldValue = EmpDSO.Recordset.Fields(window.event.srcElement.Name)
  newValue = window.event.srcElement.Value

  output = "Modified HTML element : " & window.event.srcElement.Name & vbcrlf
  output = output & "Old Value : " & oldValue & vbcrlf
  output = output & "New Value : " & newValue

  MsgBox output

End Function

Function AftUpdate()
  MsgBox "XML after update : " & vbcrlf & EmpDSO.xml
End Function

</SCRIPT>

<html>

<title>Employee Information</title>

<BODY>

<xml id=EmpDSO>
<Employees>
  <Employee><EmpID>E001</EmpID><EmpName>Jack</EmpName></Employee>
</Employees>
</xml>

<INPUT datasrc=#EmpDSO datafld="EmpID" Id="EmpID" Name="EmpId" onbeforeupdate="BefUpdate" onafterupdate="AftUpdate"> <BR>
<INPUT datasrc=#EmpDSO datafld="EmpName" Id="EmpName" Name="EmpName" onbeforeupdate="BefUpdate" onafterupdate="AftUpdate">

</BODY>

</html>

Open BeforeAfterUpdate.htm in Internet Explorer, and note that the values in the EmpID and EmpName fields from the single record in the XML DSO are displayed in the bound HTML Textbox elements.
Change the value that are displayed in the HTML Textbox element that are bound to the EmpName field, and then tab out of the textbox. This action causes the BefUpdate and AftUpdate VbScript functions to fire in sequence for the EmpName HTML Textbox element.
The code in the BefUpdate VbScript function first displays the DSO's XML with data that existed before you made the change to the EmpName field. It then displays the name of the data field that was modified (EmpName, in this instance) along with its data before and after the value change. The code uses the DSO's Recordset object to access the field's pre-update value. It then accesses the Value property of the HTML element that raised the onbeforeupdate event (the HTML Textbox element bound to the DSO's EmpName field) to obtain the new value that was entered into the Textbox element. Accessing the new value by using the HTML element that raised the event requires the bound HTML element to be assigned a Name that is identical to the name of the field in the XML DSO. Accessing both the old and new values of a data field before the update is posted makes it possible to implement custom routines to validate the new data and to roll back to the old data if required. For instance, use the BefUpdate VbScript function in the preceding sample to reset the EmpName field back to its original value when the new value is identified to be a blank string, as shown in the following code:
```
Function BefUpdate()
  
  Dim oXMLNode 
  Dim oldValue
  Dim newValue
  Dim output

  oldValue = EmpDSO.Recordset.Fields(window.event.srcElement.Name)
  newValue = window.event.srcElement.Value

  if newvalue = "" then 
     Msgbox "EmpName cannot be blank"
     window.event.srcElement.Value = oldvalue
  End if

End Function
					
```
The onafterupdate event that is fired after onbeforeupdate triggers the AftUpdate() VBScript function, which displays the DSO's XML with the modified data.

PRB: Accessing Data Changes in the OnCellChange Event Procedure (283182)

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Steps to Reproduce Behavior