IDebugExpressionEvaluator3::Parse2

Artikkeli
01/12/2024

Converts an expression string to a parsed expression given the symbol provider and the address of the evaluating frame.

Syntax

HRESULT Parse2 (
    string                     upstrExpression,
    enum_PARSEFLAGS            dwFlags,
    uint                       nRadix,
    IDebugSymbolProvider       pSymbolProvider,
    IDebugAddress              pAddress,
    out string                 pbstrError,
    out uint                   pichError,
    out IDebugParsedExpression ppParsedExpression
);

HRESULT Parse2 (
    LPCOLESTR                upstrExpression,
    PARSEFLAGS               dwFlags,
    UINT                     nRadix,
    IDebugSymbolProvider*    pSymbolProvider,
    IDebugAddress*           pAddress,
    BSTR*                    pbstrError,
    UINT*                    pichError,
    IDebugParsedExpression** ppParsedExpression
);

Parameters

upstrExpression
[in] The expression string to be parsed.

dwFlags
[in] A collection of PARSEFLAGS constants that determine how the expression is to be parsed.

nRadix
[in] Radix to be used to interpret any numerical information.

pSymbolProvider
[in] Interface of the symbol provider.

pAddress
[in] Address of the evaluating frame.

pbstrError
[out] Returns the error as human-readable text.

pichError
[out] Returns the character position of the start of the error in the expression string.

ppParsedExpression
[out] Returns the parsed expression in an IDebugParsedExpression object.

Return Value

If successful, returns S_OK; otherwise, returns an error code.

Remarks

This method produces a parsed expression, not an actual value. A parsed expression is ready to be evaluated, that is, converted to a value.

Example

The following example shows how to implement this method for a CEE object that exposes the IDebugExpressionEvaluator3 interface.

HRESULT CEE::Parse2 ( LPCOLESTR in_szExprText,
  PARSEFLAGS in_FLAGS,
  UINT in_RADIX,
  IDebugSymbolProvider *pSymbolProvider,
  IDebugAddress *pAddress,
  BSTR* out_pbstrError,
  UINT* inout_pichError,
  IDebugParsedExpression** out_ppParsedExpression )
{
    // precondition
    REQUIRE( NULL != in_szExprText );
    //REQUIRE( NULL != out_pbstrError );
    REQUIRE( NULL != inout_pichError );
    REQUIRE( NULL != out_ppParsedExpression );

    if (NULL == in_szExprText)
        return E_INVALIDARG;

    if (NULL == inout_pichError)
        return E_POINTER;

    if (NULL == out_ppParsedExpression)
        return E_POINTER;

    if (out_pbstrError)
        *out_pbstrError = NULL;

    *out_ppParsedExpression = NULL;

    INVARIANT( this );

    if (!this->ClassInvariant())
        return E_UNEXPECTED;

    // function body
    EEDomain::fParseExpression DomainVal =
    {
        this,                   // CEE*
        in_szExprText,          // LPCOLESTR
        in_FLAGS,               // EVALFLAGS
        in_RADIX,               // RADIX
        out_pbstrError,         // BSTR*
        inout_pichError,        // UINT*
        pSymbolProvider,
        out_ppParsedExpression  // Output
    };

    return (*m_LanguageSpecificUseCases.pfParseExpression)(DomainVal);
}

Jaa