dbates.Spry.Eval is a set of utilities for evaluating arithmetic expressions.
* In its preferred emobodiment, the class attribute "dbates.Spry.Eval" is added to every tag
* whose text body should be evaluated. For instance,
* ** {x} => substitutes the value of the node whose id is x. *L:, W: * {l}*{w}*
* To evaluate all apropriate elements on a page, call {@link dbates.Spry.Eval.evaluate()}. *
* Optionally, you can pass a set of options to the constructor dbates.Spry.Eval. You must call the * constructor in the page
. ** The following are valid options: *
true if expressions should be evaluated on page load; false otherwise.
*
* Upon evaluation, dbates.Spry.Eval will assign an id to the ambient container element of the
* expression if an id is not already present.The assigned id will have the form
* dbates:Spry:Eval:resultX where X >= 0 in the order in which expressions are encountered during
* pre-order traversal of the document tree.
*
* For example: * 2*3 => 6 * 7*{dbates:Spry:Eval:result0} => 42 */ var dbates; if (!dbates) dbates = {}; if (!dbates.Spry) dbates.Spry = {}; if (!dbates.Spry.Util) dbates.Spry.Util = {}; if (!dbates.Spry.Util.EventHandlers) dbates.Spry.Util.EventHandlers = new Array(); dbates.Spry.Eval = function(opts) { dbates.Spry.Util.EventHandler.addEventHandler(window, "load", function () { dbates.Spry.Eval.init(opts); }); }; dbates.Spry.Eval.CLASS_NAME = "dbates:Spry:Eval"; dbates.Spry.Eval.NodeArray = new Array(); dbates.Spry.Eval.errorValue = 0; dbates.Spry.Eval.init = function(opts) { if (opts && opts.errorValue) dbates.Spry.Eval.errorValue = opts.errorValue; nodes = dbates.Spry.Util.getNodesByFunc(document,function (node) { return (dbates.Spry.Util.hasClassNamed(node, dbates.Spry.Eval.CLASS_NAME)); }); var numNodes = nodes.length; var count = 0; for (var i = 0; i < numNodes; ++i) { var expr = dbates.Spry.Eval.getExpressionForNode(nodes[i]); if (!expr) { var obj = dbates.Spry.Eval.createObjectForNode(nodes[i]) if (!obj) continue; if (opts && opts.evaluateFieldOn) { var evalOpts = opts.evaluateFieldOn; var numEvaluationOpts = evalOpts.length; for (var j = 0; j < numEvaluationOpts; ++j) dbates.Spry.Eval.addEventListener(nodes[i], evalOpts[j]); } dbates.Spry.Eval.NodeArray.push(obj); if (opts && opts.evaluateOnLoad) dbates.Spry.Eval.setNodeValue(nodes[i], dbates.Spry.Eval.evaluateStr(dbates.Spry.Eval.getNodeValue(nodes[i]))); else if (opts && opts.initialValue) dbates.Spry.Eval.setNodeValue(nodes[i], opts.initialValue); else dbates.Spry.Eval.setNodeValue(nodes[i], 0); try{ if (!nodes[i].hasAttribute("id")) nodes[i].setAttribute("id", dbates.Spry.Eval.CLASS_NAME+":result_"+(count++)); } catch (e) {} } } }; dbates.Spry.Eval.evaluate = function(element) { element = (element)? $(element) : document; nodes = dbates.Spry.Util.getNodesByFunc(element,function (node) { return (dbates.Spry.Util.hasClassNamed(node, dbates.Spry.Eval.CLASS_NAME)); }); var numNodes = nodes.length; for (var i = 0; i < numNodes; ++i) { var expr = dbates.Spry.Eval.getExpressionForNode(nodes[i]); if (expr) { dbates.Spry.Eval.setNodeValue(nodes[i], dbates.Spry.Eval.evaluateStr(expr)); } else { var obj = dbates.Spry.Eval.createObjectForNode(nodes[i]) if (!obj) continue; dbates.Spry.Eval.NodeArray.push(obj); dbates.Spry.Eval.setNodeValue(nodes[i], dbates.Spry.Eval.evaluateStr(dbates.Spry.Eval.getNodeValue(nodes[i]))); } var elementHandler = dbates.Spry.Util.EventHandler.getEventHandler(nodes[i], "change"); if (elementHandler) elementHandler.handleEvent(); } }; dbates.Spry.Eval.createObjectForNode = function(node) { var obj = new Object(); if (!obj) return null; obj[0] = node; obj[1] = dbates.Spry.Eval.getNodeValue(node); return obj; }; dbates.Spry.Eval.getExpressionForNode = function(node) { for (var i = 0; i < dbates.Spry.Eval.NodeArray.length; ++i) { var obj = dbates.Spry.Eval.NodeArray[i]; if (obj && obj[0] == node) return obj[1]; } return null; }; dbates.Spry.Eval.setExpressionForNode = function(node, expr) { for (var i = 0; i < dbates.Spry.Eval.NodeArray.length; ++i) { var obj = dbates.Spry.Eval.NodeArray[i]; if (obj && obj[0] == node){ obj[1] = expr; break; } } }; dbates.Spry.Eval.evaluateStr = function(regionStr) { try { var result = eval(dbates.Spry.Eval.sub_params(regionStr)); if (isNaN(result)) result = dbates.Spry.Eval.errorValue; return result; } catch (e) { return dbates.Spry.Eval.errorValue; } }; dbates.Spry.Eval.sub_params = function(regionStr) { if (!regionStr) return ""; var resultStr = ""; var re = new RegExp("\\{([^\\}:]+::)?[^\\}]+\\}", "g"); var startSearchIndex = 0; while (startSearchIndex < regionStr.length) { var reArray = re.exec(regionStr); if (!reArray || !reArray[0]) { resultStr += regionStr.substr(startSearchIndex, regionStr.length - startSearchIndex); return resultStr; } if (reArray.index != startSearchIndex) resultStr += regionStr.substr(startSearchIndex, reArray.index - startSearchIndex); var dsName = ""; if (reArray[0].search(/^\{[^}:]+::/) != -1) dsName = reArray[0].replace(/^\{|::.*/g, ""); var fieldName = reArray[0].replace(/^\{|.*::|\}/g, ""); var ref = null; if (dsName != "") { var formObj = eval("document."+dsName); if (eval("document."+dsName)) ref = eval("document."+dsName+"."+fieldName); } else ref = $(fieldName); if (ref && ref.nodeName == "INPUT") { var _value = parseFloat(ref.value.toString().replace(/\$|\,/g,'')); resultStr += (isNaN(_value))? 0 : _value; } else if (ref) { var _value = parseFloat(ref.innerHTML.toString().replace(/\$|\,/g,'')); resultStr += (isNaN(_value))? 0 : _value; } else if (fieldName == "pi") { resultStr += "3.14159265358979323844"; } else if (fieldName == "e") { resultStr += "2.71828182845904523536"; } else { resultStr += "0"; } if (startSearchIndex == re.lastIndex) { var leftOverIndex = reArray.index + reArray[0].length; if (leftOverIndex < regionStr.length) resultStr += regionStr.substr(leftOverIndex); break; } startSearchIndex = re.lastIndex; } return resultStr; }; dbates.Spry.Eval.getNodeValue = function (node) { if (!node) return null; var result; if (node.nodeName == "INPUT" || node.nodeName == "TEXTAREA") result = node.value; else if (node.nodeName == "SELECT") result = node.options[node.selectedIndex].value; else if (dbates.Spry.Util.hasClassNamed(node, dbates.Spry.Eval.CLASS_NAME)) result = node.innerHTML; return result; }; dbates.Spry.Eval.setNodeValue = function (node, value) { if (!node) return; if (node.nodeName == "INPUT" || node.nodeName == "TEXTAREA") node.value = value; else if (node.nodeName == "SELECT") return; else if (dbates.Spry.Util.hasClassNamed(node, dbates.Spry.Eval.CLASS_NAME)) node.innerHTML = value; }; dbates.Spry.Eval.addEventListener = function(element, eventType) { if (!element) return ""; var regionStr = dbates.Spry.Eval.getNodeValue(element); if (!regionStr) return ""; var resultStr = ""; var re = new RegExp("\\{([^\\}:]+::)?[^\\}]+\\}", "g"); var startSearchIndex = 0; while (startSearchIndex < regionStr.length) { var reArray = re.exec(regionStr); if (!reArray || !reArray[0]) { resultStr += regionStr.substr(startSearchIndex, regionStr.length - startSearchIndex); return resultStr; } if (reArray.index != startSearchIndex) resultStr += regionStr.substr(startSearchIndex, reArray.index - startSearchIndex); var dsName = ""; if (reArray[0].search(/^\{[^}:]+::/) != -1) dsName = reArray[0].replace(/^\{|::.*/g, ""); var fieldName = reArray[0].replace(/^\{|.*::|\}/g, ""); var ref = null; if (dsName != "") { var formObj = eval("document."+dsName); if (eval("document."+dsName)) ref = eval("document."+dsName+"."+fieldName); } else ref = $(fieldName); if (ref && ref.nodeName == "INPUT") { var elementHandlerObj = dbates.Spry.Util.EventHandler.addEventHandler(element, eventType, null, true); var handlerObj = dbates.Spry.Util.EventHandler.addEventHandler(ref, eventType, function(u) { dbates.Spry.Eval.evaluate(element); }, false); handlerObj.addEventListener(function(u) { elementHandlerObj.handleEvent(); }); } else if (ref && dbates.Spry.Util.hasClassNamed(ref, dbates.Spry.Eval.CLASS_NAME)) dbates.Spry.Util.EventHandler.addEventHandler(ref, eventType, function(u) { dbates.Spry.Eval.evaluate(element); }, true); startSearchIndex = re.lastIndex; } }; /* HELPER ROUTINES. */ dbates.Spry.Eval.getTokensFromStr = function(str) { if (!str) return null; return str.match(/{[^}]+}/g); }; dbates.Spry.Util.getNodesByFunc = function(root, func) { var nodeStack = new Array; var resultArr = new Array; var node = root; while (node) { if (func(node)) resultArr.push(node); if (node.hasChildNodes()) { nodeStack.push(node); node = node.firstChild; } else { if (node == root) node = null; else try { node = node.nextSibling; } catch (e) { node = null; }; } while (!node && nodeStack.length > 0) { node = nodeStack.pop(); if (node == root) node = null; else try { node = node.nextSibling; } catch (e) { node = null; } } } if (nodeStack && nodeStack.length > 0) // Error. return; return resultArr; }; dbates.Spry.Eval.getElementsByClassName = function(node, className) { var result = new Array(); var elemList = node.childNodes; if (elemList) { for (var i = 0; i < elemList.length; ++i) { if (elemList.item(i).className == className) result.push(elemList.item(i)); } } return result; }; dbates.Spry.Eval.getElementsByClassAndTag = function(node, className, tagName) { if (!document.getElementsByTagName) return; if (!tagName) var tagName = '*'; if (!node) var node = document; var result = new Array(); var elemList = node.getElementsByTagName(tagName); if (elemList) { for (var i = 0; i < elemList.length; ++i) { if (elemList.item(i).className == className) result.push(elemList.item(i)); } } return result; }; dbates.Spry.Util.addEventListener = function(element, eventType, handler, capture) { try { element = $(element); if (element.addEventListener) element.addEventListener(eventType, handler, capture); else if (element.attachEvent) element.attachEvent("on" + eventType, handler); } catch (e) {} }; dbates.Spry.Util.hasClassNamed = function(node, className) { if (!node) return; try{ var classes = node.className.split(' '); var num_classes = classes.length; for (var i = 0; i < num_classes; ++i) if (classes[i] == className) return true; return false; } catch(e) { return false} }; /* Event Handler. */ dbates.Spry.Util.EventHandler = function (element, eventType) { this.element = element; this.eventType = eventType; this.isAttached = false; this.listeners = new Array(); }; dbates.Spry.Util.EventHandler.prototype.addEventListener = function(handler) { this.listeners.push(handler); }; dbates.Spry.Util.EventHandler.prototype.attach = function() { if (this.isAttached) return; var _this = this; dbates.Spry.Util.addEventListener(this.element, this.eventType, function () { _this.handleEvent(); }, false); this.isAttached = true; }; dbates.Spry.Util.EventHandler.prototype.handleEvent = function() { var num_listeners = this.listeners.length; for (var i = 0; i < num_listeners; ++i) { var listener = this.listeners[i]; listener(this.element); } }; dbates.Spry.Util.EventHandler.getEventHandler = function(element, eventType) { var num_handlers = dbates.Spry.Util.EventHandlers.length; for (var i = 0; i < num_handlers; ++i) { if (dbates.Spry.Util.EventHandlers[i].element == element && dbates.Spry.Util.EventHandlers[i].eventType == eventType) return dbates.Spry.Util.EventHandlers[i]; } return null; }; dbates.Spry.Util.EventHandler.addEventHandler = function(element, eventType, handler, isVirtualEvent) { var handlerObj = dbates.Spry.Util.EventHandler.getEventHandler(element, eventType); if (!handlerObj) { handlerObj = new dbates.Spry.Util.EventHandler(element, eventType); dbates.Spry.Util.EventHandlers.push(handlerObj); } if (handlerObj && handler) handlerObj.addEventListener(handler); if (!isVirtualEvent) handlerObj.attach(); return handlerObj; }; /* Other routines. */ function $() { var elements = new Array(); for (var i = 0; i < arguments.length; i++) { var element = arguments[i]; if (typeof element == 'string') element = document.getElementById(element); if (arguments.length == 1) return element; elements.push(element); } return elements; };