Cette fois, je vais vous apporter un graphique linéaire des changements de performances dans la production h5. Quelles sont les précautions pour créer un graphique linéaire des changements de performances dans h5. Ce qui suit est un cas pratique, prenons un. regarder.
En définissant dynamiquement la hauteur de l'élément intérieur =>
<!DOCTYPE html><html><head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>示例1</title>
<style>
#title { margin: 2px; font-family: Helvetica, Arial, sans-serif; font-size: 9px; font-weight: bold; line-height: 15px; color: rgb(0, 255, 255);
} #demo { width: 74px; height: 30px; background: rgb(0, 255, 255); margin: 2px
} span.col { width: 1px; height: 100%; float: left; opacity: 0.9; background: rgb(0, 0, 34);
} </style></head><body>
<div style=" opacity: 0.9; cursor: pointer; position: absolute; top: 0px;margin: 10px; background: rgb(0, 0, 34);">
<div id="title"></div>
<div id="demo"></div>
</div>
<script>
function fillLineChart(id) { this.id = id; this.el = document.getElementById(id); this.value = 0;//当前值
this.width = parseInt(this.el.clientWidth) this.last=this.width-1;//从左往右最后一个span的索引
for (var i = 0; i < this.width; i++) {//初始化span
this.el.innerHTML +='<span class="col"></span>';
} this.draw = function (value) {//绘制事件
this.value = value;//记录当前值
for (var i = 0; i <this.last; i++) {//遍历前x-1个,将后一个值赋给前一个
var tmph = this.el.getElementsByTagName("span")[i + 1].style.height;//获取下一个值
this.el.getElementsByTagName("span")[i].style.height = tmph;//赋给当前的
} this.el.getElementsByTagName("span")[this.last].style.height = parseInt(this.el.clientHeight) * (100 - this.value) / 100 + "px";//设置最后span一个高度=span容器的高度x值百分比
}
} var demo = new fillLineChart("demo"); var val = 0
setInterval(function () {
val = rand(rand(20, 50), 60); document.getElementById('title').innerHTML = `示例(${val})`
demo.draw(val);
}, 100); function rand(begin, end) { return Math.floor(Math.random() * (end - begin)) + begin;
} </script></body></html>Copier après la connexion
2 Par Canvas =>[Exemple]
<!DOCTYPE html><html><head>
<meta charset="UTF-8">
<title>示例2</title>
<style>
#title { margin: 2px; font-family: Helvetica, Arial, sans-serif; font-size: 9px; font-weight: bold; line-height: 15px; color: rgb(0, 255, 255);
} #demo {
margin: 2px
} span.col { width: 1px; height: 100%; float: left; opacity: 0.9; background: rgb(0, 0, 34);
} </style></head><body>
<div style=" opacity: 0.9; cursor: pointer; position: absolute; top: 0px;margin: 10px; background: rgb(0, 0, 34);">
<div id="title"></div>
<canvas id="demo" width="74" height="30"></canvas>
</div>
<script>
function fillLineChart(id) { this.id = id; this.canvas = document.getElementById(id); this.value = 0; this.width = (this.canvas.clientWidth)//获取Copier après la connexion
Largeur de reliure
.
this.height = (this.canvas.clientHeight) //获取高度宽度
this.context = this.canvas.getContext("2d"); this.values = []; this.last = this.width - 1;//最后一个值的索引
for (var i = 0; i < this.width; i++) {//初始化值
this.values.push(this.height);
} this.draw = function (value) { this.value = value;//记录当前值
this.context.clearRect(0, 0, this.width, this.height);//清空
this.context.beginPath();//开辟新的绘制路径
this.context.moveTo(0, this.height);//绘制起点
for (var i = 0; i <this.last; i++) { this.values[i] = this.values[i + 1];//移动索引值
this.context.lineTo(i, this.values[i]);//结束位置
} this.values[this.last] = this.height * (100 - value) / 100;//获取最后索引一个值
this.context.lineTo(this.last, this.values[this.last]);//设置最后一个索引位置
this.context.lineTo(i, this.height);//绘制结束
this.context.fillStyle = ' rgb(0, 255, 255)';//填充绘制区域的颜色
this.context.fill();//填充
}
} var demo = new fillLineChart("demo"); var val = 0
setInterval(function () {
val = rand(rand(20, 50), 60); document.getElementById('title').innerHTML = `示例(${val})`
demo.draw(val);
}, 100); function rand(begin, end) { return Math.floor(Math.random() * (end - begin)) + begin;
} </script></body></html>Copier après la connexion
3.Canvas enhancement=>[Exemple]
<!DOCTYPE html><html><head>
<meta charset="UTF-8">
<title>示例3</title>
<style>
#title {margin: 2px; font-family: Helvetica, Arial, sans-serif; font-size: 9px; font-weight: bold; line-height: 15px; color: rgb(0, 255, 255);}
#demo {margin: 2px}
span.col { width: 1px; height: 100%; float: left; opacity: 0.9; background: rgb(0, 0, 34);} </style></head><body>
<label ><input type="checkbox" onclick="demo.isFull=this.checked" checked/>填充显示</label>
<div style=" opacity: 0.9; cursor: pointer; position: absolute; top: 30px;margin: 10px; background: rgb(0, 0, 34);">
<div id="title"></div>
<canvas id="demo"></canvas>
</div>
<script>
function lineChart(o) { this.id = o.id; this.canvas = document.getElementById(o.id); this.color = o.color || 'rgb(0, 255, 255)'; this.value = 0; this.isFull = o.isFull || false;//是否填充颜色
this.canvas.width = this.width = o.width || (this.canvas.clientWidth);//获取绑定宽度
this.canvas.height = this.height = o.height || (this.canvas.clientHeight);//获取高度宽度
this.context = this.canvas.getContext("2d"); this.values = []; this.last = this.width - 1;//最后一个值的索引
for (var i = 0; i < this.width; i++) {//初始化值
this.values.push(this.height);
} this.draw = function (value) { this.value = value;//记录当前值
this.context.clearRect(0, 0, this.width, this.height);//清空
this.context.beginPath();//开辟新的绘制路径
this.context.moveTo(0, this.isFull ? this.height : this.values[1]);//绘制起点
for (var i = 0; i < this.last; i++) { this.values[i] = this.values[i + 1];//移动索引值
this.context.lineTo(i, this.values[i]);//结束位置
} this.values[this.last] = this.height * (100 - value) / 100;//获取最后索引一个值
this.context.lineTo(this.last, this.values[this.last]);//设置最后一个索引位置
if (this.isFull) { this.context.lineTo(i, this.height);//绘制结束
this.context.fillStyle = this.color;//填充绘制区域的颜色
this.context.fill();//填充
} else { this.context.strokeStyle = this.color; this.context.stroke();
}
}
} var demo = new lineChart({ id: "demo", width: "74", height: "30", isFull: true,
}); var val = 0
setInterval(function () {
val = rand(rand(20, 50), 60); document.getElementById('title').innerHTML = `示例(${val})`
demo.draw(val);
}, 100); function rand(begin, end) { return Math.floor(Math.random() * (end - begin)) + begin;
} </script></body> </html>Copier après la connexion
Je pense que vous maîtrisez la méthode après avoir lu le cas dans cet article. Pour un contenu plus passionnant, veuillez payer. attention aux autres sites Web chinois php Articles connexes !
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