动态加载

js

function initform()
{
 selectlayer(document.forms[0].layertype);
 loadComboSpec("../ComboServlet","tbllayertype","id","name",document.forms[0].layertype);
 loadComboSpec("../ComboServlet","viewlayertype","id","name",document.forms[0].group);
 loadComboSpec("../ComboServlet","viewlayertype","id","name",document.forms[0].subgroup);
}
function loadComboSpec(servletPath,tableName,idField,nameField,combo)
{
 var strX="<root>";
 strX+="<_session>s</_session>";
 strX+="<__tableName>"+tableName+"</__tableName>";
 strX+="<__id>"+idField+"</__id>";
 strX+="<__name>"+nameField+"</__name>";
 strX+="<_pageCount>-1</_pageCount>";
 strX+="</root>";
 var strReturn=cSendHttp(servletPath,strX);
 var oXML1=new ActiveXObject("Microsoft.XMLDOM");
 oXML1.async="false";
 oXML1.loadXML( strReturn);
 var root = oXML1.documentElement;
 try
 {
  for (i=1;i<root.childNodes.length;i++)
  {
   strSValue=root.childNodes.item(i).childNodes.item(0).text;
   strSText=root.childNodes.item(i).childNodes.item(1).text;
   if(strSValue!=null)
   {
    combo.length=combo.length+1;
    combo.options[combo.length-1].text=strSText;
    combo.options[combo.length-1].value=strSValue;
   }
  }
 }catch(exception)
 {}
}

servlet :

import java.io.DataInputStream;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.*;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import org.w3c.dom.Document;
import org.w3c.dom.Element;

public class ComboServlet extends HttpServlet
{

    private static final String CONTENT_TYPE = "text/xml; charset=UTF-8";

    public ComboServlet()
    {
    }

    public void doPost(HttpServletRequest request, HttpServletResponse response)
        throws IOException, ServletException
    {
        try
        {
            response.setContentType("text/xml; charset=UTF-8");
            DocumentBuilderFactory dbfac = DocumentBuilderFactory.newInstance();
            DocumentBuilder builder = dbfac.newDocumentBuilder();
            DataInputStream is = new DataInputStream(request.getInputStream());
            Document doc = builder.parse(is);
            String str = doc.getDocumentElement().getAttribute("action");
            Input input = new XmlInput(doc);
            ServletOutputStream out = response.getOutputStream();
            Element el = null;
            if(input.getParameter("__id") != null && !input.getParameter("__id").equals(""))
                el = TableClass.getResult(input.getParameter("__tableName"), new String[] {
                    input.getParameter("__id"), input.getParameter("__name")
                }, new String[] {
                    input.getParameter("__name")
                }, input).toXML(null);
            else
            if(input.getParameter("__tableName").equals("tblpermission"))
                el = TableClass.getResult(input.getParameter("__tableName"), new String[] {
                    "id", "descript"
                }, new String[] {
                    "descript", "id"
                }, input).toXML(null);
            else
                el = TableClass.getResult(input.getParameter("__tableName"), new String[] {
                    "id", "name"
                }, new String[] {
                    "name", "id"
                }, input).toXML(null);
            if(el == null)
                el = builder.newDocument().createElement("Informations");
            StreamResult sr = new StreamResult(out);
            TransformerFactory tf = TransformerFactory.newInstance();
            Transformer t = tf.newTransformer();
            t.setOutputProperty("encoding", "UTF-8");
            DOMSource doms = new DOMSource(el);
            t.transform(doms, sr);
            out.flush();
        }
        catch(Exception ex)
        {
            ex.printStackTrace();
        }
    }