Hi,Scenario:–I have four fields(combo box) say, A,B,C,B for example in a web application.
I have to get values using a view in the same database using
AJAX dbcolumn and dblookup.
Field A–dbcolumn.
Field B–dblookup(based up on the value choosen in A field).
Field C–dblookup(based up on the value choosen in B field).
Field D–dblookup(based up on the value choosen in C field).
Problem:-- How to perform muliple dblookups using AJAX.
Subject: Multiple lookups using ajax
Load your first combo box A normally with @dbcolumn.2. Then onChange() of A write the ajax script and populate combo B.
Then onChange() of B write the ajax script and populate combo C.
Then onChange() of C write the ajax script and populate combo D.
When not a new doc and in edit mode you need to make sure to write up a script onLoad() of the form to again get the values for B, C, D and repopulate them and also make sure to select the value previously selected.
HTH
Sai
Subject: RE: Multiple lookups using ajax
At first thank you for your help,but I am facing the following problem.
Error(s):-- If I call the dblookup function in the onchange event of “B” combo box(which is inheriting the values based upon"A"combo box using dblookup) then the code fails.
Problem:-- What are the changes that has to be made to use the following code for multiple dblookups i.e for fields “C”, “D”
Code:–Following is the code that i have used to get the
Dbcolumn and dblookup for A and B fields.
var req;
var attr;
var xmlkey;
var resultColXML= new Array()
var resultlkpXML= new Array()
var ObjCombo1;
var ObjCombo2;
var lkpKey;
/*---------------------------
Dbcolumn function start here
-------------------*/
function dbColumn(server,path,view,column,ObjCombo1)
{
ObjCombo1=A
//Put your first combo name here to get dbcolumn result
var pos=0;
currURL =(document.location.href).toLowerCase();
if (trim(server) == “”)
{
pos = currURL.indexOf(‘://’);
if (pos < 0 )
server = “http://10.10.10.120”
// Put your server name here
else
{
pos += 3;
pos = currURL.indexOf(‘/’, pos);
server = currURL.substring(0, pos)
alert(server)
}
}
if( trim(path) == “” )
{
if( pos > 0 )
{
newPos = currURL.indexOf('.nsf',pos);
if (newPos > 0)
{
path = currURL.substring
(pos+1,newPos+4)
}
}
}
if( !isNaN(column) )
column -= 1;
vurl = “/”+trim(path)+“/”+view+“?Readviewentries”
//checking whether browser is Mozila or Netscape
if (window.XMLHttpRequest)
{
req = new XMLHttpRequest();
req.overrideMimeType(‘text/xml’);
req.onreadystatechange =
processReqChange_Col;
req.open(“GET”, vurl , true);
req.send(null);
}
//checking whether browser is IE
else if (window.ActiveXObject)
{
req = new ActiveXObject(“Microsoft.XMLHTTP”);
if (req)
{
req.onreadystatechange = processReqChange_Col;
req.open(“GET”, vurl, true);
req.send();
}
}
}
/* Function used to check whether XML file loaded completely or not */
function processReqChange_Col()
{
if (req.readyState == 4)
/*Only process if XML file is loaded completely:4=“Complete” */
{
if (req.status == 200)
/Only process if everything is ok/
{
response = req.responseXML.
documentElement;
populateColumn(response)
}
else
{
alert(“There was a problem retrieving the XML data:n” + req.statusText);
}
}
}
/* Function used to extract value one by one from XML file */
function populateColumn(responseXML)
{
NodeList = responseXML.getElementsByTagName(“viewentry”)
for (var k=0;k<NodeList.length;k+=1)
{
child =
responseXML.getElementsByTagName
(‘text’)[k].firstChild
while (child != null)
{
filterNode =
responseXML.getElementsByTagName(“viewentry”)
var filterItem = filterNode.item(k);
posNumber = filterItem.getAttribute(“position”);
if (( child.nodeType == 3) &&
(posNumber.indexOf(“.”)==-1))
{
resultColXML[k] = trim(child.nodeValue);
}
child = child.nextSibling
}
}
var finalresult= new Array()
var tmpstr="";
var sep="";
for (var p=0;p<resultColXML.length;p++)
{
if (resultColXML[p] != ‘’ && resultColXML[p] != null )
{
tmpstr =tmpstr+sep+trim(resultColXML[p])
sep="#"
}
}
finalresult = tmpstr.split(“#”)
writeInCombo(finalresult,ObjCombo1)
}
/* Function used to trim string */
function trim(str)
{
return str.replace(/^s+/g, ‘’).replace(/s+$/g, ‘’);
}
/*---------------------------
writing in combo function start here
-------------------*/
function writeInCombo(data,fldCombo)
{
fldCombo.length=0
fldCombo.length +=1
fldCombo[fldCombo.length-1].text = “–Select–”
for(iCount=0;iCount<data.length;iCount++)
{
fldCombo.length +=1
strText=data[iCount]
if (strText !=undefined && strText != null)
{
fldCombo[fldCombo.length-1].text = trim(strText)
}
}
}
/*---------------------------
Dblookup function start here
-------------------*/
function dbLookup(server,path,view,key,column,ProjCode0)
{
lkpKey=key
ObjCombo2=B
//Put your second combo name here to get dblookup result
var pos=0;
currURL = (document.location.href).toLowerCase();
if (trim(server) == “”)
{
pos = currURL.indexOf(‘://’);
if (pos < 0 )
server = “http://10.10.10.120”
// Put your server name here
else
{
pos += 3;
pos = currURL.indexOf(‘/’, pos);
server = currURL.substring(0, pos)
alert(server)
}
}
if( trim(path) == “” )
{
if( pos > 0 )
{
newPos = currURL.indexOf('.nsf',pos);
if (newPos > 0)
{
path = currURL.substring(pos+1,newPos+4)
}
}
}
if( !isNaN(column) )
column -= 1;
vurl = “/”+trim(path)+“/”+view+“?Readviewentries&restricttocategory=”+lkpKey
//checking whether browser is mozila or Netscape
if (window.XMLHttpRequest)
{
req = new XMLHttpRequest();
req.overrideMimeType(‘text/xml’);
req.onreadystatechange = processReqChange_lookup;
req.open(“GET”, vurl , true);
req.send(null);
}
//checking whether browser is IE
else if (window.ActiveXObject)
{
req = new ActiveXObject(“Microsoft.XMLHTTP”);
if (req)
{
req.onreadystatechange =processReqChange_lookup;
req.open(“GET”, vurl, true);
req.send();
}
}
}
/* Function used to check whether
XML file loaded completely or not */
function processReqChange_lookup()
{
if (req.readyState == 4)
/*Only process if XML
file is loaded completely:4=“Complete” */
{
if (req.status == 200)
/Only process if everything is ok/
{
response = req.responseXML.documentElement;
populatelookup(response)
}
else
{
alert(“There was a problem retrieving the XML data:n” + req.statusText);
}
}
}
/* Function used to extract
value one by one from XML file */
function populatelookup(responseXML)
{
NodeList =
responseXML.getElementsByTagName(“viewentry”)
var tmplkpstr="";
var sep="";
for(var i=0; i<NodeList.length; i++)
{
tmplkpstr =
tmplkpstr+sep+NodeList[i].getElementsByTagName
(“text”)[0].childNodes[0].nodeValue
sep=“#”
}
finallkpresult = tmplkpstr.split(“#”)
writeInCombo(finallkpresult,ObjCombo2)
}
On load event:–
ObjCombo1=document.forms[0].A;
ObjCombo2=document.forms[0].B;
dbColumn(“http://10.10.10.120”,“xxx.nsf”,“vwView”,1,ObjCombo1)
On change event:–(combo box “A”)
keyVal=ObjCombo1.options
[ObjCombo1.selectedIndex].text;
ObjCombo2.length=0
dbLookup(“http://10.10.10.120”,“LT-New/LTWeb.nsf”,“vwProjects”,keyVal,2,ObjCombo2)