大部分參考：原文地址

首先定義幾個變數：

var paper =null;

var dragger=null;

var move=null;

var up=null;

var shapes=null;

var mouseX=null;//儲存頁面中滑鼠的X軸座標

var mouseY=null;//儲存頁面中滑鼠的Y軸座標

var r=null;

var objCrr=null;

var mouse=null;//儲存頁面中滑鼠的屬性

var connections=[];//用來儲存節點的順序

$(function(){

$("#holder").mousemove(function(obj){

moush=obj;

moushX=obj.clientX;

moushY=obj.clientY;

if(objCrr!=null){

r.drawArr(objCrr);

}

})

//拖動節點開始時的事件
            var dragger = function () {
                this.ox = this.attr("x");
                this.oy = this.attr("y");
                this.animate({ "fill-opacity": .2 }, 500);
            };

 //拖動事件
            var move = function (dx, dy) {
                var att = { x: this.ox + dx, y: this.oy + dy };
                this.attr(att);
                $("#test" + this.id).offset({ top: this.oy + dy + 10, left: this.ox + dx + 10 });
                for (var i = connections.length; i--; ) {
                    r.drawArr(connections[i]);
                }
            };
            //拖動結束後的事件
            var up = function () {
                this.animate({ "fill-opacity": 0 }, 500);
            };
            //建立繪圖物件
            var r = Raphael("holder", $(window).width(), $(window).height());
            //繪製節點
            var shapes = [
                        r.rect(190, 100, 60, 40, 4),
                        r.rect(290, 80, 60, 40, 4),
                        r.rect(290, 180, 60, 40, 4),
                        r.rect(450, 100, 60, 40, 4)
                     ];
            //定位節點上的文字
            $("#test1").offset({ top: 100 + 10, left: 190 + 10 });
            $("#test2").offset({ top: 80 + 10, left: 290 + 10 });
            $("#test3").offset({ top: 180 + 10, left: 290 + 10 });
            $("#test4").offset({ top: 100 + 10, left: 450 + 10 });
            //為節點新增樣式和事件，並且繪製節點之間的箭頭
            for (var i = 0, ii = shapes.length; i < ii; i++) {
                var color = Raphael.getColor();
                shapes[i].attr({ fill: color, stroke: color, "fill-opacity": 0, "stroke-width": 2, cursor: "move" });
                shapes[i].id = i + 1;
                shapes[i].drag(move, dragger, up);

shapes[i].click(click);
shapes[i].dblclick(function () { alert(this.id) })

}

 //儲存節點間的順序
   connections.push(r.drawArr({ obj1: shapes[0], obj2: shapes[1] }));
   connections.push(r.drawArr({ obj1: shapes[1], obj2: shapes[2] }));
   connections.push(r.drawArr({ obj1: shapes[2], obj2: shapes[3] }));     

})

var startNode=null;//兩個節點連線時，儲存開始的節點

var saveNode=new Array();//儲存兩個節點

var tempArrPath=[];//兩個點連線時用於暫時儲存起始節點到滑鼠的線段

function click(){

svaeNode.push(this);

if(saveNode.length==1){

startNode=this;

}

if(saveNode.length==2){

if(tempArrPath[0]!=undefined){

tempArrPath[0].arrPath.remove();

saveNode.splice(0,2);

objCrr={obj1:startNode,obj2:this};

connections.push(r.drawArr(objCrr));

}else{

startNode=this;

saveNode.splice(0,2);

saveNode.push(this);

}

}

}

在拖動事件中，動態改變了節點文字元素的位置

並且重繪了節點和箭頭

drawArr是一個自定義方法，負責修改箭頭的方向，程式碼如下

//隨著節點位置的改變動態改變箭頭
        Raphael.fn.drawArr = function (obj) {

if(obj.ibj2==null){

           var point = getStartEnd(obj.obj1, obj.obj2);
            var path1 = getArr(point.start.x, point.start.y, mouseX, mouseY-10, 8);
            for(var i=0;i<tempArrPath.Length;i++){

                tempArrPath[i].arrPath.remove();

            }

   tempArrPath=[];

  obj.arrPath=this.path(path2);

obj.arrPath.attr({"stroke-width":2});

tempArrPath.push(obj);

return;

}else{

            tempArrPath.splice(0,tempArrPath.Length);

            var point = getStartEnd(obj.obj1, obj.obj2);
            var path1 = getArr(point.start.x, point.start.y, point.end.x, point.end.y, 8);
            if (obj.arrPath) {
                obj.arrPath.attr({ path: path1 });
            } else {
                obj.arrPath = this.path(path1);
            }
            return obj;

}
        

};

首先需要確定箭頭的起始位置，

point包含兩個點，

point.start為起點,

point.end為終點，

然後需要確定箭頭的繪圖路徑

一個箭頭包含三個線段，四個點

1:起點，2:終點，3:箭頭終點1，4:箭頭終點2

在此函式中，判斷如果箭頭已經被繪製過，

只要修改屬性即可

如果沒有被繪製過，則需要重新繪製

下面來看一下動態確定起點和終點的程式碼

function getStartEnd(obj1, obj2) {
            var bb1 = obj1?bj1.getBBox():null;
                bb2 = obj2?j2.getBBox():null;
            var p = [

                    bb1?{ x: bb1.x + bb1.width / 2, y: bb1.y - 1 }:{},
                    bb1?{ x: bb1.x + bb1.width / 2, y: bb1.y + bb1.height + 1 }:{},

                    bb1?{ x: bb1.x - 1, y: bb1.y + bb1.height / 2 }:{},
                    bb1?{ x: bb1.x + bb1.width + 1, y: bb1.y + bb1.height / 2 }:{},
                    bb2?{ x: bb2.x + bb2.width / 2, y: bb2.y - 1 }:{},
                    bb2?{ x: bb2.x + bb2.width / 2, y: bb2.y + bb2.height + 1 }:{},
                    bb2?{ x: bb2.x - 1, y: bb2.y + bb2.height / 2 }:{},
                    bb2?{ x: bb2.x + bb2.width + 1, y: bb2.y + bb2.height / 2 }:{},
                    
                    
                ];
            var d = {}, dis = [];
            for (var i = 0; i < 4; i++) {
                for (var j = 4; j < 8; j++) {
                    var dx = Math.abs(p[i].x - p[j].x),
                        dy = Math.abs(p[i].y - p[j].y);
                    if (
                         (i == j - 4) ||
                         (((i != 3 && j != 6) || p[i].x < p[j].x) &&
                         ((i != 2 && j != 7) || p[i].x > p[j].x) &&
                         ((i != 0 && j != 5) || p[i].y > p[j].y) &&
                         ((i != 1 && j != 4) || p[i].y < p[j].y))
                       ) {
                        dis.push(dx + dy);
                        d[dis[dis.length - 1]] = [i, j];
                    }
                }
            }
            if (dis.length == 0) {
                var res = [0, 4];
            } else {
                res = d[Math.min.apply(Math, dis)];
            }
            var result = {};
            result.start = {};
            result.end = {};
            result.start.x = p[res[0]].x;
            result.start.y = p[res[0]].y;
            result.end.x = p[res[1]].x;
            result.end.y = p[res[1]].y;
            return result;
        }

if(startNode==null){

alert("還沒有選擇節點"); return -1;

}else{

objCrr={obj1:startNode,obj2:null};

}

//獲取組成箭頭的三條線段的路徑
        function getArr(x1, y1, x2, y2, size) {
            var angle = Raphael.angle(x1, y1, x2, y2);//得到兩點之間的角度
            var a45 = Raphael.rad(angle - 45);//角度轉換成弧度
            var a45m = Raphael.rad(angle + 45);
            var x2a = x2 + Math.cos(a45) * size;
            var y2a = y2 + Math.sin(a45) * size;
            var x2b = x2 + Math.cos(a45m) * size;
            var y2b = y2 + Math.sin(a45m) * size;
            var result = ["M", x1, y1, "L", x2, y2, "L", x2a, y2a, "M", x2, y2, "L", x2b, y2b];
            return result;
        }

頁面

<input type="button" onclick="addLine()" value="新增線條"/>

<div id="holder"></div>

<div id="test1" class="test">測試1</div>

<div id="test2" class="test">測試2</div>

<div id="test3" class="test">測試3</div>

<div id="test4" class="test">測試4</div>