golang处理gb2312转utf-8编码的问题

body, err = iconv.ConvertString(body, "GBK", "utf-8")

func ConvertString(input string, fromEncoding string, toEncoding string) (output string, err error) {  // create a temporary converter  converter, err := NewConverter(fromEncoding, toEncoding)
  if err == nil {    // convert the string    output, err = converter.ConvertString(input)
    // close the converter    converter.Close()  }
  return}

NewConverter(fromEncoding, toEncoding)

output, err = converter.ConvertString(input)

type Converter struct {  context C.iconv_t  open    bool}
// Initialize a new Converter. If fromEncoding or toEncoding are not supported by// iconv then an EINVAL error will be returned. An ENOMEM error maybe returned if// there is not enough memory to initialize an iconv descriptorfunc NewConverter(fromEncoding string, toEncoding string) (converter *Converter, err error) {  converter = new(Converter)
  // convert to C strings  toEncodingC := C.CString(toEncoding)  fromEncodingC := C.CString(fromEncoding)
  // open an iconv descriptor  converter.context, err = C.iconv_open(toEncodingC, fromEncodingC)
  // free the C Strings  C.free(unsafe.Pointer(toEncodingC))  C.free(unsafe.Pointer(fromEncodingC))
  // check err  if err == nil {    // no error, mark the context as open    converter.open = true  }
  return}

converter.context, err = C.iconv_open(toEncodingC, fromEncodingC)

The empty encoding name "" is equivalent to "char": it denotes the locale dependent character encoding.
When the string "//TRANSLIT" is appended to tocode, transliteration is activated. This means that when a character cannot  be  represented  in  the  targetcharacter set, it can be approximated through one or several similarly looking characters.
When the string "//IGNORE" is appended to tocode, characters that cannot be represented in the target character set will be silently discarded.
The resulting conversion descriptor can be used with iconv any number of times. It remains valid until deallocated using iconv_close.
A  conversion descriptor contains a conversion state. After creation using iconv_open, the state is in the initial state. Using iconv modifies the descrip-tor's conversion state. (This implies that a conversion descriptor can not be used in multiple threads simultaneously.) To bring the state back to the ini-tial state, use iconv with NULL as inbuf argument.

ConvertString(input string, fromEncoding string, toEncoding string)NewConverter(fromEncoding string, toEncoding string) (converter *Converter, err error)C.iconv_open(toEncodingC, fromEncodingC)

body, err = iconv.ConvertString(body, "GBK", "utf-8//IGNORE")

body, err = iconv.ConvertString(body, "GBK", "utf-8//IGNORE")