uni-app通過生成UUID，生成圖形驗證碼

S4() {
				return (((1 + Math.random()) * 0x10000) | 0).toString(16).substring(1);
			},
			guid() {
				return (this.S4() + this.S4() + "-" + this.S4() + "-" + this.S4() + "-" + this.S4() + "-" + this.S4() + this.S4() +
					this.S4());
			},
			async genImgCode() {
				let uuid = "cms" + this.guid();
				this.codeImg = this.$serverUrl + '/captcha.jpg?uuid=' + uuid;
			}