XML/HTML Code復(fù)制內(nèi)容到剪貼板
- <html>
- <canvas id="a_canvas" width="1000" height="700"></canvas>
- <script>
-
- (function (){
-
- window.addEventListener("load", function(){
-
- var data = [100,-1000,0,700];
-
- // 獲取上下文
- var a_canvas = document.getElementById('a_canvas');
- var context = a_canvas.getContext("2d");
-
-
- // 繪制背景
- var gradient = context.createLinearGradient(0,0,0,300);
-
-
- // gradient.addColorStop(0,"#e0e0e0");
- //gradient.addColorStop(1,"#ffffff");
-
-
- context.fillStyle = gradient;
-
- context.fillRect(0,0,a_canvas.width,a_canvas.height);
-
-
- // 描繪邊框
- var grid_cols = data.length + 1;
- var grid_rows = 4;
- var cell_height = a_canvas.height / grid_rows;
- var cell_width = a_canvas.width / grid_cols;
- context.lineWidth = 1;
- context.strokeStyle = "#a0a0a0";
-
- // 結(jié)束邊框描繪
- context.beginPath();
- // 準(zhǔn)備畫(huà)橫線(xiàn)
- /*for (var col = 0; col <= grid_cols; col++) {
- var x = col * cell_width;
- context.moveTo(x,0);
- context.lineTo(x,a_canvas.height);
- }
- // 準(zhǔn)備畫(huà)豎線(xiàn)
- for(var row = 0; row <= grid_rows; row++){
- var y = row * cell_height;
- context.moveTo(0,y);
- context.lineTo(a_canvas.width, y);
- }*/
- //劃?rùn)M線(xiàn)
- context.moveTo(0,a_canvas.height/2);
- context.lineTo(a_canvas.width,a_canvas.height/2);
-
- //畫(huà)豎線(xiàn)
- context.moveTo(0,0);
- context.lineTo(0,a_canvas.height);
-
-
- context.lineWidth = 1;
- context.strokeStyle = "#c0c0c0";
- context.stroke();
-
- var max_v =0;
-
- for(var i = 0; i<data.length; i++){
- var d=0;
- if(data[i]<0)
- {dd=d-data[i];
- }
- else{d=data[i];};
- if (d > max_v) { max_v =d};
- }
- max_vmax_v = max_v * 1.1;
- // 將數(shù)據(jù)換算為坐標(biāo)
- var points = [];
- for( var i=0; i < data.length; i++){
- var v= data[i];
- var px = cell_width * (i +1);
- var py = a_canvas.height/2 - a_canvas.height*(v / max_v)/2;
- points.push({"x":px,"y":py});
- }
- // 繪制折現(xiàn)
- context.beginPath();
- context.moveTo(points[0].x, points[0].y);
- for(var i= 1; i< points.length; i++){
- context.lineTo(points[i].x,points[i].y);
- }
-
-
- context.lineWidth = 2;
- context.strokeStyle = "#8BA9FF";
- context.stroke();
-
- //繪制坐標(biāo)圖形
- for(var i in points){
- var p = points[i];
- context.beginPath();
- context.arc(p.x,p.y,4,0,2*Math.PI);
- //實(shí)心圓
- /*
- context.fillStyle = "#000";*/
- //空心圓
- context.strokeStyle = "#000";
- context.stroke();
- context.fillStyle="white";
- context.fill();
- }
- //添加文字
- for(var i in points)
- { var p = points[i];
- context.beginPath();
- context.fillStyle="black";
- context.fillText(data[i], p.x + 1, p.y - 15);
-
- }
- },false);
- })();
-
-
- </script>
- </html>
以上這篇用html5繪制折線(xiàn)圖的實(shí)例代碼就是小編分享給大家的全部?jī)?nèi)容了，希望能給大家一個(gè)參考，也希望大家多多支持腳本之家。
