本文所舉的例子與保存HTML格式數(shù)據(jù)至XML類似。在以往當(dāng)表格被提交后，我們通常會創(chuàng)建一個新的文檔，現(xiàn)在只要文檔已經(jīng)存在，那么直接添加就可以了。此種技術(shù)的使用與創(chuàng)建基本數(shù)據(jù)類似。
在前面的文章里，我已經(jīng)演示了如何使用XMLDOM。因此，我們可以直接進入本文的示例。
我們需要考慮的第一件事是我們將用于添加新"記錄"的HTML 表單。在"將HTML表單數(shù)據(jù)保存至XML"例子中我們已使用過此表單，只是更改了文件名，但代碼是相同的。
AddContact.html:
復(fù)制代碼 代碼如下:
html>
head>
title> Contact Information /title>
/head>
body>
form action="processAdd.asp" method="post">
h3>Enter your contact information/h3>
First Name:
input type="text" id="firstName" name="firstName">br> Last Name:
input type="text" id="lastName" name="lastName">br> Address #1:
input type="text" id="address1" name="address1">br> Address #2:
input type="text" id="address2" name="address2">br> Phone Number:
input type="text" id="phone" name="phone">br> E-Mail:
input type="text" id="email" name="email">br>
input type="submit" id="btnSub" name="btnSub" value="Submit">br>
/form>
/body>
/html>
我們設(shè)置此HTML表單是來處理ADD。ASP的。這里的ASP 頁面具有檢測XML.文件及ROLODEX.XML是否存在的功能。如果它們確實存在，ASP則會在文件上附加新的條目，如果文件不存在，則需要創(chuàng)建。
Process Add.asp:
復(fù)制代碼 代碼如下:
%
'--------------------------------------------------------------------
'The "addNewContacttoXML" Function accepts two parameters.
'strXMLFilePath - The physical path where the XML file will be saved.
'strFileName - The name of the XML file that will be saved.
'--------------------------------------------------------------------
Function addNewContacttoXML(strXMLFilePath, strFileName)
'Declare local variables.
Dim objDom
Dim objRoot
Dim objRecord
Dim objField
Dim objFieldValue
Dim objattID
Dim objattTabOrder
Dim objPI
Dim blnFileExists
Dim x
'Instantiate the Microsoft XMLDOM.
Set objDom = server.CreateObject("Microsoft.XMLDOM")
objDom.preserveWhiteSpace = True
'Call the Load Method of the XMLDOM Object. The Load ethod has a
'boolean return value indicating whether or not the file could be
'loaded. If the file exists and loads it will return true, otherwise,
'it will return false.
blnFileExists = objDom.Load(strXMLFilePath "\" strFileName)
'Test to see if the file loaded successfully.
If blnFileExists = True Then
'If the file loaded set the objRoot Object equal to the root element
'of the XML document.
Set objRoot = objDom.documentElement Else
'Create your root element and append it to the XML document.
Set objRoot = objDom.createElement("rolodex")
objDom.appendChild objRoot
End If
'Create the new container element for the new record.
Set objRecord = objDom.createElement("contact")
objRoot.appendChild objRecord
'Iterate through the Form Collection of the Request Object.
For x = 1 To Request.Form.Count
'Check to see if "btn" is in the name of the form element. If it is,
'then it is a button and we do not want to add it to the XML
'document".
If instr(1,Request.Form.Key(x),"btn") = 0 Then
'Create an element, "field".
Set objField = objDom.createElement("field")
'Create an attribute, "id".
Set objattID = objDom.createAttribute("id")
'Set the value of the id attribute equal the the name of the current
'form field.
objattID.Text = Request.Form.Key(x)
'The setAttributeNode method will append the id attribute to the
'field element. objField.setAttributeNode objattID
'Create another attribute, "taborder". This just orders the
'elements.
Set objattTabOrder = objDom.createAttribute("taborder")
'Set the value of the taborder attribute.
objattTabOrder.Text = x
'Append the taborder attribute to the field element.
'objField.setAttributeNode objattTabOrder
'Create a new element, "field_value".
Set objFieldValue = objDom.createElement("field_value")
'Set the value of the field_value element equal to the value of the
'current field in the Form Collection.
objFieldValue.Text = Request.Form(x)
'Append the field element as a child of the new record container
'element, contact. objRecord.appendChild objField
'Append the field_value element as a child of the field element.
objField.appendChild objFieldValue
End If
Next
'Check once again to see if the file loaded successfully. If it did
'not, that means we are creating a new document and need to be sure to
'insert the XML processing instruction.
If blnFileExists = False then
'Create the xml processing instruction.
Set objPI = objDom.createProcessingInstruction("xml", "version='1.0'")
'Append the processing instruction to the XML document.
objDom.insertBefore objPI, objDom.childNodes(0)
End If
'Save the XML document.
objDom.save strXMLFilePath "\" strFileName
'Release all of your object references.
Set objDom = Nothing
Set objRoot = Nothing
Set objRecord = Nothing
Set objField = Nothing
Set objFieldValue = Nothing
Set objattID = Nothing
Set objattTabOrder = Nothing
Set objPI = NothingEnd
Function
'Do not break on an error.
On Error Resume Next
'Call the addNewContacttoXML function, passing in the physical path to
'save the file to and the name that you wish to use for the file.
addNewContacttoXML "c:","rolodex.xml"
'Test to see if an error occurred, if so, let the user know.
'Otherwise, tell the user that the operation was successful.
If err.number > 0 then
Response.write("Errors occurred while saving your form submission.")
Else
Response.write("Your form submission has been saved.")
End If
%>
如果你已經(jīng)讀過關(guān)于"將HTML 表單數(shù)據(jù)保存至XML格式"的文章，你會注意到附加到將HTML數(shù)據(jù)擴展到XML文件的代碼與HTML數(shù)據(jù)擴展到新文檔的代碼基本上是一致的。但是這里還是有兩個主要的不同點：
'Call the Load Method of the XMLDOM Object. The Load Method has a
'boolean return value indicating whether or not the file could be
'loaded. If the file exists and loads it will return true, otherwise,
'it will return false.
blnFileExists = objDom.Load(strXMLFilePath "\" strFileName)
'Test to see if the file loaded successfully.
If blnFileExists = True Then
'If the file loaded set the objRoot Object equal to the root element
'of the XML document.
Set objRoot = objDom.documentElement
Else
'Create your root element and append it to the XML document.
Set objRoot = objDom.createElement("contact")
objDom.appendChild objRoot
End If
本節(jié)的代碼來自addNewContacttoXML 功能。因為我們不可能每次都新建一個文件，所以我們改為保存CONTACT。如果能夠LOAD此文件呢，我們則獲得了這個XML文檔的根元素；如果不能夠呢，那么我們就假設(shè)它不存在并創(chuàng)建一個新的要元素并將它附加到XML文檔上。
另外一個主要區(qū)別在于：當(dāng)我們對文件進行二次檢測，是否成功的LOAD，這樣我們可以決定是否需要加上 一條處理指令。如果文件存在，我們就不需要加上這條指令。但是，如果創(chuàng)建了一個新的文件，那么則一定得加上這條處理指令。
'Check once again to see if the file loaded successfully. If it did
'not, that means we are creating a new document and need to be sure to
'insert the XML processing instruction.
If blnFileExists = False then
'Create the xml processing instruction.
Set objPI = objDom.createProcessingInstruction("xml", "version='1.0'")
'Append the processing instruction to the XML document.
objDom.insertBefore objPI, objDom.childNodes(0)
End If
除開以上兩點不同之處外，你可以發(fā)現(xiàn) 保存數(shù)據(jù)至新文件的代碼實際上是與 附加新record至存在文件的代碼是一樣的。我們創(chuàng)建一個新的element, contact CONTAINER，以便能容下每個新添的RECORD。代碼將會在Form Collection of the Request Objec中不斷重復(fù)以創(chuàng)建適合的XML節(jié)點并將這些節(jié)點值設(shè)置得與當(dāng)前Form Field.一樣。
如以往一樣，我推薦大家復(fù)制以上代碼至你的 服務(wù)器上并運行。希望以上舉例會對你有所幫助。
