var ctx = canvas.get(0).getContext("2d")；我就想知道这get（0）啥意思啊

Question

var ctx = canvas.get(0).getContext("2d");

canvas.attr("width",$(window).get(0).innerWidth);

canvas.attr("height",$(window).get(0).innerHeight);

$(window).resize(resizeCanvas);

function resizeCanvas(){

     canvas.attr("width",$(window).get(0).innerWidth);

     canvas.attr("height",$(window).get(0).innerHeight);     

};

Answer 1

有多个canvas，取第一个