JS：如何正确绘制文字

drawChar: function(oneChar, x, y) {
    if (canvas.getContext) {
        var g2d = canvas.getContext("2d");  //2d用引用括起来
    }
    if (!context) {
        return;
    }
    drawText = String.fromCharCode(oneChar); 
    g2d.save();
    g2d.beginPath();
    g2d.moveTo(100, 100);
    g2d.lineTo(800, 800);
    // 设置画笔的颜色和大小
    g2d.fillStyle   = "red";   // 填充颜色为红色
    g2d.strokeStyle = "blue";  // 画笔的颜色
    g2d.lineWidth   = 5;       // 指定描边线的宽度
    // 写字
    g2d.font = "28px 宋体";
    g2d.fillText(drawText, x, y);
    g2d.closePath();
    g2d.stroke();
    g2d.restore();
}