小程序输入框字数统计

        //1、文本输入

        change(event){

            let _cursor = this.getByteLen(event.detail.value);

            this.setData({text:event.detail.value,count:_cursor})

        },

        //2、获取字符串长度（汉字算两个字符，字母数字算一个）

        getByteLen(val) {

            var len = 0;

            for (var i = 0; i < val.length; i++) {

                var a = val.charAt(i);

                if (a.match(/[^\x00-\xff]/ig) != null) {

                    len += 1;

                }

                else {

                    len += 1;

                }

            }

            if(len>=500){

                return 500;

            }else{

                return len;

            }

        },