问题描述：

自定义组件内实现canvas保存图片，canvas绘图正常，获取临时路径时客户端直接闪退

//获取临时路径

getTempFilePath: function (canvasId) {

let tempUrl = '';

var _this = this;

wx.canvasToTempFilePath({

canvasId: canvasId,

success: (res) => {

tempUrl = res.tempFilePath;

},

fail: (error) => {

console.log(error)

}

},this)