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Reading headers in a WSP buffer

TWspField object holds the name and value pair of the WSP header field. TWspHeaderSegmenter pulls the header / value pair out of the WSP buffer (into TWspField ). Call TWspHeaderSegmenter::NextL() to iterate through the WSP buffer. It calls TWspPrimitiveDecoder .

CWspHeaderEncoder allows you to encode the values and parameters of the header field. It creates one header at a time from the name / value pairs.

The following are the steps to encode the WSP header:

Create a header encoder object.

        //creates a pointer to CWspHeaderEncoder object
CWspHeaderEncoder* primEncoder = CWspHeaderEncoder::NewLC();

Start a new encoded header to encode the parameter value.

        // start a new encoded header
primEncoder->StartHeaderL(0x27);

Call CWspHeaderEncoder::StartValueLengthL() to calculate the length of encodings that are added subsequently. The value calculated, is stored as part of the encoded string, as specified in the WSP standard.
```
        primEncoder->StartValueLengthL();
       
```

Encode the header field and add it to the encoded field. Note : The appropriate WSP method is used for encoding the header field of a data type such as integer, date, text string and so on.

        primEncoder->AddIntegerL(0x7F);
primEncoder->AddUintVarL(0xff);
primEncoder->AddLongIntL(999999);
_LIT8(KString, "WSP Encode: String");
primEncoder->AddTextStringL(KString);
TDateTime time(2006,EMarch,20,06,36,30,000000); //create a date time object
primEncoder->AddDateL(time); // add 
TUInt intVal=489;
primEncoder->AddLTokenL(intVal);
_LIT8(KTokenText, "WSP Encode: Token Text");
primEncoder->AddLTokenTextL(KTokenText);

Call CWspHeaderEncoder::EndValuesLengthL() at the time of header construction when ValueLength can be calculated.
Assuming that the length of the header encodings has been calculated and added to the encoder field, call CWspHeaderEncoder::EndValuesLengthL() .
```
        primEncoder->EndValueLengthL();
       
```
Call CWspHeaderEncoder::EndHeaderL() , to complete the header encoding. This completes and returns the encoded header field's 8 bit buffer. EndHeaderL() panics if EndValueLengthL() is not called after CWspHeaderEncoder::StartValueLengthL() .
```
        HBufC8* buf = primEncoder->EndHeaderL();
       
```
This returns a pointer to the buffer containing the encoded field.

Parent topic: Encoding and Decoding WSP Headers