最近一段时间忽然想到用javascript理论上可以实现一个复杂的在线编辑器,完全能够支持词法、语法方面的功能,于是试验了一下...效率和简易程度还是令人吃惊的,看来javascript比想象的还要强大...
<html> <head> <title>Silverna Demo Ver 0.01</title> <style> div.editbox{ margin:0 0 0 0; padding:0 0 0 0; font:16/18px Arial; border:0px solid #000000; } p{ margin:0 0 0 0; padding:0 0 0 0; } </style> </head>
<body style="margin:0 0 0 0;padding:0 0 0 0;word-break:break-all;overflow-x:hidden" onload="editbox.focus()"> <div id="editbox" class="editbox" style="width:99%;height:80%;" contentEditable="true" onkeyDown="return KeyDown()" onkeyUp="KeyUp()" onclick="getCursorPosition()"> </div> <select size="10" style="display:none;position:absolute" id="methods" onkeydown="SelectMethod()" onclick="SelMethod(this)"> </body> </html>
</select> <script language=JScript> var testArray = new Array(); var testDate = new Date(); var testString = "aaa"; var testVal = 1; var testObj = new myObj;
function myObj() { myObj.prototype.testFunc = function(){}; this.testProperty = "test"; } function KeyDown() { //alert(event.altKey); if(event.keyCode == 9) //TAB 键 { clipboardData.setData(‘text‘,‘ ‘); event.srcElement.document.execCommand(‘paste‘); return false; } if(event.keyCode == 8) //Backspace 键 { var oSel = document.selection.createRange(); var offset = event.srcElement.document.selection.createRange(); offset.moveToPoint(oSel.offsetLeft, oSel.offsetTop); offset.moveStart(‘character‘, -4); if(offset.text.length < 4) return true; for (var i = 0; i < offset.text.length; i++) { if (offset.text.charAt(i) != " ") { return true; } } offset.select(); event.srcElement.document.execCommand(‘Delete‘); return false; } return true; }
function KeyUp() { var oSel, offset; if(event.keyCode == 13) { testStr = event.srcElement.innerText.substring(0, getCursorPosition()); //alert(testStr); var space = ""; for (var i = testStr.length - 1; i >= 0; i--) { //alert(testStr.length+":"+testStr.charAt(i) + ":" + space.length); if (testStr.charAt(i) == "\n") break; if (testStr.charAt(i) == " ") space += " "; else space = ""; } //alert(testStr); clipboardData.setData(‘text‘,space); event.srcElement.document.execCommand(‘paste‘); } oSel = document.selection.createRange(); var left = oSel.offsetLeft; var top = oSel.offsetTop; var token = getCurrentToken(event.srcElement); var chars = getCursorPosition();
parseSyntax(event.srcElement); offset = event.srcElement.document.selection.createRange(); offset.moveToPoint(left, top); offset.select();
if(event.keyCode == 190) //.键 { setMethods(token.posTok.slice(0, -1)); } }
function parseSyntax(src) //解析当前文本 { var text = src.innerHTML; text = text.replace(/<FONT[^<>]*>/gi, "").replace(/<\/FONT[^<>]*>/gi,""); text = text.replace(/<P>/gi, "\xfe").replace(/<\/P>/gi, "\xff"); text = text.replace(/\ /gi, "\xfd"); text = text.replace(/\r\n/gi,""); for (var i = 0; i <SyntaxSet.All.length; i++) { var syntaxes = SyntaxSet.All[i]; for (var j = 0; j < syntaxes.rules.All.length; j++) { syntaxes.rules.All[j].color = syntaxes.color; syntaxes.rules.All[j].cons = syntaxes.cons;
text = parseRule(text, syntaxes.rules.All[j]); } }
src.innerHTML = text.replace(/\xfc/g,"‘").replace(/\xfe/g,"<P>").replace(/\xff/g,"</P>").replace(/\xfd/g," "); } function parseRule(text, rule) //解析词法 { //利用正则表达式 var newText = "";
var idx = text.search(rule.expr);
while (idx != -1) { var remark = text.match(rule.expr); //alert(text.substring(0, idx+remark[0].length)); var subText = text.substring(0, idx + remark[0].length);
if(rule.cons == null || (idx == 0 || rule.cons.test(text.charAt(idx-1))) && (idx + remark[0].length >= text.length || rule.cons.test(text.charAt(idx + remark[0].length)))) { //alert(remark[0]); //alert(remark[0].replace(/<FONT[^<>]*>/gi, "").replace(/<\/FONT[^<>]*>/gi,"")); subText = subText.replace(remark[0], "<FONT color=\xfc"+rule.color+"\xfc>" + remark[0].replace(/<FONT[^<>]*>/gi, "").replace(/<\/FONT[^<>]*>/gi,"") + "</FONT>"); //alert(subText); } newText += subText; text = text.substring(idx + remark[0].length); idx = text.search(rule.expr); } newText += text; return newText; }
function getCurrentToken(src) { var oSel = document.selection.createRange(); var offset = src.document.selection.createRange(); offset.moveToPoint(oSel.offsetLeft, oSel.offsetTop); offset.moveStart("character", -99999);
var tokens = offset.text.split(/[\s\+\-\*\/]/); //token由连续字母数字、下划线、点号、括号、引号构成 var currentToken = tokens[tokens.length - 1];
var idx = offset.text.length;
var fullToken = src.innerText.substring(idx); fullToken = fullToken.replace(/[\s\+\-\*\/]/,"@@@@");
idx = fullToken.indexOf("@@@@"); if(idx != -1) fullToken = fullToken.substring(0, idx);
var token = new Array();
token.currentToken = currentToken + fullToken; token.posTok = currentToken;
return token; } Array.prototype.pushDistinct = function(obj) { for (var i = 0; i < this.length; i++) { if (this[i] == obj) { return null; } } this.push(obj); return obj; }
function putMethods(methodList, obj, methods) //将方法添加到方法列表 { var list = methods.split(",");
for (var i = 0; i < list.length; i++) { if (obj[list[i]] != null) { methodList.pushDistinct(list[i]); } } } var now = new Date(); //测试用 var a = 33.3333; //测试用 var __expr = new RegExp("tt"); //测试用 function setMethods(objStr) { var oSel = document.selection.createRange();
try { if (objStr == "alert") return; var methodList = new Array(); var obj = eval(objStr);
if (obj.prototype != null) { methodList.pushDistinct("prototype"); } if (obj != null) {
//基本Object方法 putMethods(methodList, obj,"constructor,hasOwnProperty,isPrototypeOf,propertyIsEnumerable,toLocaleString,toString,valueOf"); //基本Array方法 putMethods(methodList, obj,"concat,join,length,pop,push,reverse,shift,slice,sort,splice,unshift");
//基本Date方法 putMethods(methodList,obj,"getDate,getUTCDate,getDay,getUTCDay,getFullYear,getUTCFullYear,getHours,getUTCHours,getMilliseconds,getUTCMilliseconds,getMinutes,getUTCMinutes,getMonth,getUTCMonth,getSeconds,getUTCSeconds,getTime,getTimezoneoffset,getYear");
putMethods(methodList,obj,"setDate,setUTCDate,setFullYear,setUTCFullYear,setHours,setUTCHours,setMilliseconds,setUTCMilliseconds,setMinutes,setUTCMinutes,setMonth,setUTCMonth,setSeconds,setUTCSeconds,setTime,setYear,toDateString,toGMTString,toLocaleDateString,toLocaleTimeString,toString,toTimeString,toUTCString,valueOf,parse,UTC");
//基本Math方法 putMethods(methodList,obj,"E,LN10,LN2,LOG10E,LOG2E,PI,SQRT1_2,SQRT2"); putMethods(methodList,obj,"abs,acos,asin,atan,atan2,ceil,cos,exp,floor,log,max,min,pow,random,round,sin,sqrt,tan");
//基本Function方法 putMethods(methodList,obj,"arguments,caller,length,prototype,apply,call,toString"); //基本Number方法 putMethods(methodList,obj,"MAX_VALUE,MIN_VALUE,NaN,NEGATIVE_INFINITY,POSITIVE_INFINITY"); putMethods(methodList,obj,"toString,toLocalString,toFixed,toExponential,toPrecision");
//基本RegExp方法 putMethods(methodList,obj,"global,ignoreCase,lastIndex,multiline,source,exec,test");
//基本String方法 putMethods(methodList,obj,"charAt,charCodeAt,contact,indexOf,lastIndexOf,match,replace,search,slice,split,substring,substr,toLowerCase,toString,toUpperCase,valueOf,fromCharCode"); putMethods(methodList,obj,"anchor,big,blink,bold,fixed,fontcolor,fontsize,italics,link,small,strike,sub,sup");
} for (each in obj) { methodList.pushDistinct(each); } methodList.sort();
if (methodList.length > 0) { methods.options.length = 0; for (var i = 0; i < methodList.length; i++) { methods.options.add(new Option(methodList[i])); } if (methods.options.length > 10) { methods.size = 10; } else { methods.size = methods.options.length; } methods.style.top = oSel.offsetTop; methods.style.left = oSel.offsetLeft; methods.style.display = ""; methods.options[0].selected = true; methods.focus(); } } catch(e){} }
function SelectMethod() { var src = event.srcElement; if(event.keyCode == 13) { SelMethod(src); }
if(event.keyCode == 27 || event.keyCode == 8 || event.keyCode == 32) { src.style.display = "none"; editbox.focus(); } }
function SelMethod(src) { clipboardData.setData(‘text‘,src.options[src.selectedIndex].text); editbox.focus(); editbox.document.execCommand(‘paste‘); src.style.display = "none"; getCursorPosition(); } function getPos(text) //计算行数、列数 { var rows = 1; var cols = 1; var idx = 0; var subText = text; while((idx = subText.indexOf("\n")) != -1) { subText = subText.substring(idx + 1); rows++; } return new Array(rows, subText.length + 1); } function getNullRows(src,oSel) //计算空行 { var rows = 0;
var offsetEnd = src.document.selection.createRange();
var oldTop = 2; var oldLeft = 2;
while(1) { offsetEnd.moveToPoint(oSel.offsetLeft, oSel.offsetTop); offsetEnd.moveStart("character",-1-rows);
if (offsetEnd.text.length > 0 || offsetEnd.offsetTop == oldTop && offsetEnd.offsetLeft == oldLeft) { break; }
rows ++; oldTop = offsetEnd.offsetTop; oldLeft = offsetEnd.offsetLeft; } return rows; } function getCursorPosition() { var src = event.srcElement; var offset = src.document.selection.createRange(); var oSel = document.selection.createRange();
var textLength = src.innerText.length;
offset.moveToPoint(oSel.offsetLeft, oSel.offsetTop); offset.moveStart("character", -99999); //src.document.execCommand("ForeColor",false,"#ff0000"); var rowSpans = offset.getClientRects();
var pos = getPos(offset.text); var charCodes = offset.text.length; //字符总数 var chars = offset.text.replace(/\r\n/g,"").length + 1; //字符
var extRows = getNullRows(src,oSel); if(extRows > 0) { pos[0] += extRows; pos[1] = 1; } window.status = "行: " + pos[0] +", 列: " + pos[1] + ", 第 " + chars + " 个字符" + " ("+ oSel.offsetTop +","+ oSel.offsetLeft +")"; return charCodes; }
///词法解析过程................................................................................ ///............................................................................................ ///............................................................................................
var SyntaxSet = new Array(); //词法规则集合 SyntaxSet.All = new Array();
SyntaxSet.parse = function(token) //针对token返回rule { for (var i = 0; i < this.All.length; i++) { var syntaxes = this.All[i]; for (var j = 0; j < syntaxes.rules.All.length; j++) { if (syntaxes.rules.All[j].test(token)) { syntaxes.rules.All[j].color = syntaxes.color; return syntaxes.rules.All[j]; } } }
return null; }
SyntaxSet.add = function(syntaxes) { if(this[syntaxes.name] != null) return; this[syntaxes.name] = syntaxes; this.All.push(syntaxes); }
function Syntaxes(name, color, cons) //词法规则组(同组规则用一种颜色标记) { this.name = name; //规则组名称 this.color = color; //标记该语法的颜色 this.rules = new Array(); //语法规则(以次序决定优先级) this.rules.All = new Array(); this.cons = cons; //边界约束
Syntaxes.prototype.addRule = function(rule) { if(this.rules[rule.name] != null) return; this.rules[rule.name] = rule; this.rules.All.push(rule); } }
function SyntaxRule(name, regExp) //词法规则 { this.name = name; //规则名称 this.expr = regExp; //规则描述 (正则表达式) SyntaxRule.prototype.test = function(token) { return this.expr.test(token); } }
function RegExprX(exprStr) //扩展正则表达式的功能,支持定义嵌套 { this.expr = exprStr; } RegExprX.prototype.getPattern = function(tag) //获取正则表达式对象 { if (tag == null) return new RegExp(this.expr); else return new RegExp(this.expr, tag); } RegExprX.prototype.concat = function(expr, rule) //连接两个正则表达式串 { if (rule == null) this.expr += expr; //直接连接 else if (rule == "union") //联合 this.expr = "(" + this.expr + ")" + "|" + "(" + expr + ")"; else if (rule == "cons") //约束 this.expr = this.expr + "(?=" + expr + ")"; return this.expr; }
//为保证正确计算偏移量需要替换回车\n\r为\xff SyntaxSet.add(new Syntaxes("keywords", "#0000ff", /[\s\.\xfe\xff\xfd\(\{\}\)\;\,]/)); //词法?关键词?蓝色 SyntaxSet["keywords"].addRule(new SyntaxRule("Function",/function/)); SyntaxSet["keywords"].addRule(new SyntaxRule("Variable",/var/)); SyntaxSet["keywords"].addRule(new SyntaxRule("Return",/return/)); SyntaxSet["keywords"].addRule(new SyntaxRule("Exception",/(try|catch|throw)/)); SyntaxSet["keywords"].addRule(new SyntaxRule("Condition",/(if|else|switch)/)); SyntaxSet["keywords"].addRule(new SyntaxRule("Cycle",/(for|while|do)/)); SyntaxSet["keywords"].addRule(new SyntaxRule("Type",/(int|double|float|void|char)/)); SyntaxSet["keywords"].addRule(new SyntaxRule("Right",/(public|private|protected|static)/)); SyntaxSet["keywords"].addRule(new SyntaxRule("Constant",/(null|undefined|NaN|Infinity)/)); SyntaxSet["keywords"].addRule(new SyntaxRule("Construct",/(new|delete)/));
SyntaxSet.add(new Syntaxes("objects", "#FF0000", /[\s\.\xfe\xff\xfd\(\{\}\)\;\,]/)); //词法?对象?红色 SyntaxSet["objects"].addRule(new SyntaxRule("Object",/(Array|arguments|Boolean|Date|Error|Function|Object|Number|Math|RegExp|String)/));
SyntaxSet.add(new Syntaxes("global", "#800000", /[\s\.\xfe\xff\xfd\(\{\}\)\;\,]/)); //词法?系统函数?红色 SyntaxSet["global"].addRule(new SyntaxRule("SystemFunc",/(alert|parseFloat|parseInt|eval|decodeURI|decodeURIComponent|encodeURI|encodeURIComponent|escape|eval|isFinite|isNaN|unescape)/));
SyntaxSet.add(new Syntaxes("String", "#ff00ff", /[\s\.\xfe\xff\xfd\(\{\}\)\;\,\+\-\*\/]/)); //词法?字符串?粉色 SyntaxSet["String"].addRule(new SyntaxRule("String", /(‘((\\\‘)|[^\xff\‘])*([^\\\‘]|(\\\‘))‘)|("((\\\")|[^\xff\"])*([^\\\"]|(\\\"))")/));
SyntaxSet.add(new Syntaxes("remarks", "#008000")); //词法?注释?绿色 SyntaxSet["remarks"].addRule(new SyntaxRule("ShortRemark",/\/\/[^\xff]*/)); SyntaxSet["remarks"].addRule(new SyntaxRule("LongRemark",/\/\*((.*\*\/)|(.*$))/));
function Grammars() //语法规则 { } </script>
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