#### Utils
工具类

##### parseXML: (xmlStr: string, options?: OpParseXMLOptions) => any
op.utils.parseXML 用来解析 XML 字符串并返回一个 JSON 对象。

参数说明：
TODO
示例代码：
```javaScript
exports.run = async (ctx, op) => {
  const data = `
  <oauth>
    <data>
      <list>
        <name age="32">Tom</name>
      </list>
      <list>
        <name age="28">Jerry</name>
      </list>
    </data>
  </oauth>`;
  return op.utils.parseXML(data, {
    ignoreAttributes: false,
    attributeNamePrefix : "X_",
  });
};
```
以上代码返回：
```javaScript
{
  "oauth": {
    "data": {
      "list": [
        {
          "name": {
            "#text": "Tom",
            "X_age": "32",
          }
        },
        {
          "name": {
            "#text": "Jerry",
            "X_age": "28",
          }
        },
      ]
    }
  }
}

```

##### formatString: (data: any, from: string | undefined, to: string) => string
op.utils.formatString 用以将字符串在 utf8、hex、base64 等格式之间进行转换。

示例代码：
TODO

##### decodeSM4: (key: string, data: string, opts?: { mode?: string, iv?: string, inputEncoding?: string, outputEncoding?: string }) => string;
##### encodeSM4: (key: string, data: string, opts?: { mode?: string, iv?: string, inputEncoding?: string, outputEncoding?: string }) => string;

op.utils.encodeSM4 与 op.utils.decodeSM4 分别用以进行 sm4 的加解密。

参数说明：
TODO

示例代码：
```javaScript
exports.run = async (ctx, op) => {
  // 子账号加密示例
  const secret = 'YOUR_SECRET';
  const key = op.utils.formatString(secret, 'utf8', 'hex').slice(0, 32);
  const data = 'YOUR_PASSWORD';
  const encoded = '$SM4$' + op.utils.encodeSM4(key, data, { outputEncoding: 'base64' });
  log(encoded);
  // 子账号解密示例
  const decoded = op.utils.decodeSM4(key, encoded.replace(/^\$SM4\$/, ''), { inputEncoding: 'base64', outputEncoding: 'utf8' });
  log(decoded === data);
};
```