要从画布上清除图表,请删除<canvas>元素,然后将新的<canvas>元素附加到父容器,如下面的代码所示-
var resetCanvas = function(){ $('#results-graph').remove(); $('#graph-container').append('<canvas id = "results-graph"><canvas>'); canvas = document.querySelector('#results-graph'); ct = canvas.getContext('2d'); ct.canvas.width = $('#graph').width(); // here we are resizing the new canvas element to parent width ct.canvas.height = $('#graph').height(); // here we are resizing the new canvas element to parent height var a = canvas.width/2; var b = canvas.height/2; ct.font = '12pt Calibri'; ct.textAlign = 'Align Left'; ct.fillText('left aligned text on the canvas', a, b); };