C++ nsAString::Truncate方法代码示例

/* static */ bool
HTMLImageElement::SelectSourceForTagWithAttrs(nsIDocument *aDocument,
                                              bool aIsSourceTag,
                                              const nsAString& aSrcAttr,
                                              const nsAString& aSrcsetAttr,
                                              const nsAString& aSizesAttr,
                                              const nsAString& aTypeAttr,
                                              const nsAString& aMediaAttr,
                                              nsAString& aResult)
{
  MOZ_ASSERT(aIsSourceTag || (aTypeAttr.IsEmpty() && aMediaAttr.IsEmpty()),
             "Passing type or media attrs makes no sense without aIsSourceTag");
  MOZ_ASSERT(!aIsSourceTag || aSrcAttr.IsEmpty(),
             "Passing aSrcAttr makes no sense with aIsSourceTag set");

  bool pictureEnabled = HTMLPictureElement::IsPictureEnabled();
  if (aIsSourceTag && !pictureEnabled) {
    return false;
  }

  if (!IsSrcsetEnabled() || aSrcsetAttr.IsEmpty()) {
    if (!aIsSourceTag) {
      // For an <img> with no srcset, we would always select the src attr.
      aResult.Assign(aSrcAttr);
      return true;
    }
    // Otherwise, a <source> without srcset is never selected
    return false;
  }

  // Would not consider source tags with unsupported media or type
  if (aIsSourceTag &&
      ((!aMediaAttr.IsVoid() &&
       !HTMLSourceElement::WouldMatchMediaForDocument(aMediaAttr, aDocument)) ||
      (!aTypeAttr.IsVoid() &&
       !SupportedPictureSourceType(aTypeAttr)))) {
    return false;
  }

  // Using srcset or picture <source>, build a responsive selector for this tag.
  RefPtr<ResponsiveImageSelector> sel =
    new ResponsiveImageSelector(aDocument);

  sel->SetCandidatesFromSourceSet(aSrcsetAttr);
  if (pictureEnabled && !aSizesAttr.IsEmpty()) {
    sel->SetSizesFromDescriptor(aSizesAttr);
  }
  if (!aIsSourceTag) {
    sel->SetDefaultSource(aSrcAttr);
  }

  if (sel->GetSelectedImageURLSpec(aResult)) {
    return true;
  }

  if (!aIsSourceTag) {
    // <img> tag with no match would definitively load nothing.
    aResult.Truncate();
    return true;
  }

  // <source> tags with no match would leave source yet-undetermined.
  return false;
}

void
SVGScriptElement::GetScriptCharset(nsAString& charset)
{
  charset.Truncate();
}

void
nsSVGInteger::GetBaseValueString(nsAString & aValueAsString)
{
  aValueAsString.Truncate();
  aValueAsString.AppendInt(mBaseVal);
}

NS_IMETHODIMP
nsROCSSPrimitiveValue::GetCssText(nsAString& aCssText)
{
  nsAutoString tmpStr;
  aCssText.Truncate();
  nsresult result = NS_OK;

  switch (mType) {
    case CSS_PX :
      {
        float val = nsPresContext::AppUnitsToFloatCSSPixels(mValue.mAppUnits);
        nsStyleUtil::AppendCSSNumber(val, tmpStr);
        tmpStr.AppendLiteral("px");
        break;
      }
    case CSS_IDENT :
      {
        AppendUTF8toUTF16(nsCSSKeywords::GetStringValue(mValue.mKeyword),
                          tmpStr);
        break;
      }
    case CSS_STRING :
    case CSS_COUNTER : /* FIXME: COUNTER should use an object */
      {
        tmpStr.Append(mValue.mString);
        break;
      }
    case CSS_URI :
      {
        if (mValue.mURI) {
          nsAutoCString specUTF8;
          mValue.mURI->GetSpec(specUTF8);

          tmpStr.AssignLiteral("url(");
          nsStyleUtil::AppendEscapedCSSString(NS_ConvertUTF8toUTF16(specUTF8),
                                              tmpStr);
          tmpStr.AppendLiteral(")");
        } else {
          // http://dev.w3.org/csswg/css3-values/#attr defines
          // 'about:invalid' as the default value for url attributes,
          // so let's also use it here as the default computed value
          // for invalid URLs.
          tmpStr.Assign(NS_LITERAL_STRING("url(about:invalid)"));
        }
        break;
      }
    case CSS_ATTR :
      {
        tmpStr.AppendLiteral("attr(");
        tmpStr.Append(mValue.mString);
        tmpStr.Append(char16_t(')'));
        break;
      }
    case CSS_PERCENTAGE :
      {
        nsStyleUtil::AppendCSSNumber(mValue.mFloat * 100, tmpStr);
        tmpStr.Append(char16_t('%'));
        break;
      }
    case CSS_NUMBER :
      {
        nsStyleUtil::AppendCSSNumber(mValue.mFloat, tmpStr);
        break;
      }
    case CSS_DEG :
      {
        nsStyleUtil::AppendCSSNumber(mValue.mFloat, tmpStr);
        tmpStr.AppendLiteral("deg");
        break;
      }
    case CSS_GRAD :
      {
        nsStyleUtil::AppendCSSNumber(mValue.mFloat, tmpStr);
        tmpStr.AppendLiteral("grad");
        break;
      }
    case CSS_RAD :
      {
        nsStyleUtil::AppendCSSNumber(mValue.mFloat, tmpStr);
        tmpStr.AppendLiteral("rad");
        break;
      }
    case CSS_TURN :
      {
        nsStyleUtil::AppendCSSNumber(mValue.mFloat, tmpStr);
        tmpStr.AppendLiteral("turn");
        break;
      }
    case CSS_RECT :
      {
        NS_ASSERTION(mValue.mRect, "mValue.mRect should never be null");
        NS_NAMED_LITERAL_STRING(comma, ", ");
        nsCOMPtr<nsIDOMCSSPrimitiveValue> sideCSSValue;
        nsAutoString sideValue;
        tmpStr.AssignLiteral("rect(");
        // get the top
        result = mValue.mRect->GetTop(getter_AddRefs(sideCSSValue));
        if (NS_FAILED(result))
          break;
        result = sideCSSValue->GetCssText(sideValue);
//.........这里部分代码省略.........

NS_IMETHODIMP
nsXULListboxAccessible::GetRowDescription(PRInt32 aRow, nsAString& aDescription)
{
  aDescription.Truncate();
  return NS_OK;
}

NS_IMETHODIMP
nsHelperMimeType::GetDescription(nsAString& aDescription)
{
  aDescription.Truncate();
  return NS_OK;
}

NS_IMETHODIMP
ApplicationAccessible::GetActionName(PRUint8 aIndex, nsAString& aName)
{
  aName.Truncate();
  return NS_ERROR_INVALID_ARG;
}

/* readonly attribute DOMString adapterDriverDate; */
NS_IMETHODIMP
GfxInfo::GetAdapterDriverDate(nsAString & aAdapterDriverDate)
{
  aAdapterDriverDate.Truncate();
  return NS_OK;
}

NS_IMETHODIMP
nsHTMLURIRefObject::GetNextURI(nsAString & aURI)
{
  NS_ENSURE_TRUE(mNode, NS_ERROR_NOT_INITIALIZED);

  nsAutoString tagName;
  nsresult rv = mNode->GetNodeName(tagName);
  NS_ENSURE_SUCCESS(rv, rv);

  // Loop over attribute list:
  if (!mAttributes)
  {
    nsCOMPtr<nsIDOMElement> element (do_QueryInterface(mNode));
    NS_ENSURE_TRUE(element, NS_ERROR_INVALID_ARG);

    mCurAttrIndex = 0;
    element->GetAttributes(getter_AddRefs(mAttributes));
    NS_ENSURE_TRUE(mAttributes, NS_ERROR_NOT_INITIALIZED);

    rv = mAttributes->GetLength(&mAttributeCnt);
    NS_ENSURE_SUCCESS(rv, rv);
    NS_ENSURE_TRUE(mAttributeCnt, NS_ERROR_FAILURE);
    mCurAttrIndex = 0;
  }
#ifdef DEBUG_akkana
  printf("Looking at tag '%s'\n",
         NS_LossyConvertUTF16toASCII(tagName).get());
#endif
  while (mCurAttrIndex < mAttributeCnt)
  {
    nsCOMPtr<nsIDOMAttr> attrNode;
    rv = mAttributes->Item(mCurAttrIndex++, getter_AddRefs(attrNode));
    NS_ENSURE_SUCCESS(rv, rv);
    NS_ENSURE_ARG_POINTER(attrNode);
    nsString curAttr;
    rv = attrNode->GetName(curAttr);
    NS_ENSURE_SUCCESS(rv, rv);

    // href >> A, AREA, BASE, LINK
#ifdef DEBUG_akkana
    printf("Trying to match attribute '%s'\n",
           NS_LossyConvertUTF16toASCII(curAttr).get());
#endif
    if (MATCHES(curAttr, "href"))
    {
      if (!MATCHES(tagName, "a") && !MATCHES(tagName, "area")
          && !MATCHES(tagName, "base") && !MATCHES(tagName, "link"))
        continue;
      rv = attrNode->GetValue(aURI);
      NS_ENSURE_SUCCESS(rv, rv);
      nsString uri (aURI);
      // href pointing to a named anchor doesn't count
      if (aURI.First() != char16_t('#'))
        return NS_OK;
      aURI.Truncate();
      return NS_ERROR_INVALID_ARG;
    }
    // src >> FRAME, IFRAME, IMG, INPUT, SCRIPT
    else if (MATCHES(curAttr, "src"))
    {
      if (!MATCHES(tagName, "img")
          && !MATCHES(tagName, "frame") && !MATCHES(tagName, "iframe")
          && !MATCHES(tagName, "input") && !MATCHES(tagName, "script"))
        continue;
      return attrNode->GetValue(aURI);
    }
    //<META http-equiv="refresh" content="3,http://www.acme.com/intro.html">
    else if (MATCHES(curAttr, "content"))
    {
      if (!MATCHES(tagName, "meta"))
        continue;
    }
    // longdesc >> FRAME, IFRAME, IMG
    else if (MATCHES(curAttr, "longdesc"))
    {
      if (!MATCHES(tagName, "img")
          && !MATCHES(tagName, "frame") && !MATCHES(tagName, "iframe"))
        continue;
    }
    // usemap >> IMG, INPUT, OBJECT
    else if (MATCHES(curAttr, "usemap"))
    {
      if (!MATCHES(tagName, "img")
          && !MATCHES(tagName, "input") && !MATCHES(tagName, "object"))
        continue;
    }
    // action >> FORM
    else if (MATCHES(curAttr, "action"))
    {
      if (!MATCHES(tagName, "form"))
        continue;
    }
    // background >> BODY
    else if (MATCHES(curAttr, "background"))
    {
      if (!MATCHES(tagName, "body"))
        continue;
    }
    // codebase >> OBJECT, APPLET
    else if (MATCHES(curAttr, "codebase"))
//.........这里部分代码省略.........

nsresult
nsHTMLEditor::CheckPositionedElementBGandFG(nsIDOMElement * aElement,
        nsAString & aReturn)
{
    // we are going to outline the positioned element and bring it to the
    // front to overlap any other element intersecting with it. But
    // first, let's see what's the background and foreground colors of the
    // positioned element.
    // if background-image computed value is 'none,
    //   If the background color is 'auto' and R G B values of the foreground are
    //       each above #d0, use a black background
    //   If the background color is 'auto' and at least one of R G B values of
    //       the foreground is below #d0, use a white background
    // Otherwise don't change background/foreground

    aReturn.Truncate();

    nsAutoString bgImageStr;
    nsresult res =
        mHTMLCSSUtils->GetComputedProperty(aElement,
                                           nsEditProperty::cssBackgroundImage,
                                           bgImageStr);
    NS_ENSURE_SUCCESS(res, res);
    if (bgImageStr.EqualsLiteral("none")) {
        nsAutoString bgColorStr;
        res =
            mHTMLCSSUtils->GetComputedProperty(aElement,
                                               nsEditProperty::cssBackgroundColor,
                                               bgColorStr);
        NS_ENSURE_SUCCESS(res, res);
        if (bgColorStr.EqualsLiteral("transparent")) {
            nsCOMPtr<nsIDOMWindow> window;
            res = mHTMLCSSUtils->GetDefaultViewCSS(aElement, getter_AddRefs(window));
            NS_ENSURE_SUCCESS(res, res);

            nsCOMPtr<nsIDOMCSSStyleDeclaration> cssDecl;
            res = window->GetComputedStyle(aElement, EmptyString(), getter_AddRefs(cssDecl));
            NS_ENSURE_SUCCESS(res, res);

            // from these declarations, get the one we want and that one only
            nsCOMPtr<nsIDOMCSSValue> colorCssValue;
            res = cssDecl->GetPropertyCSSValue(NS_LITERAL_STRING("color"), getter_AddRefs(colorCssValue));
            NS_ENSURE_SUCCESS(res, res);

            PRUint16 type;
            res = colorCssValue->GetCssValueType(&type);
            NS_ENSURE_SUCCESS(res, res);
            if (nsIDOMCSSValue::CSS_PRIMITIVE_VALUE == type) {
                nsCOMPtr<nsIDOMCSSPrimitiveValue> val = do_QueryInterface(colorCssValue);
                res = val->GetPrimitiveType(&type);
                NS_ENSURE_SUCCESS(res, res);
                if (nsIDOMCSSPrimitiveValue::CSS_RGBCOLOR == type) {
                    nsCOMPtr<nsIDOMRGBColor> rgbColor;
                    res = val->GetRGBColorValue(getter_AddRefs(rgbColor));
                    NS_ENSURE_SUCCESS(res, res);
                    nsCOMPtr<nsIDOMCSSPrimitiveValue> red, green, blue;
                    float r, g, b;
                    res = rgbColor->GetRed(getter_AddRefs(red));
                    NS_ENSURE_SUCCESS(res, res);
                    res = rgbColor->GetGreen(getter_AddRefs(green));
                    NS_ENSURE_SUCCESS(res, res);
                    res = rgbColor->GetBlue(getter_AddRefs(blue));
                    NS_ENSURE_SUCCESS(res, res);
                    res = red->GetFloatValue(nsIDOMCSSPrimitiveValue::CSS_NUMBER, &r);
                    NS_ENSURE_SUCCESS(res, res);
                    res = green->GetFloatValue(nsIDOMCSSPrimitiveValue::CSS_NUMBER, &g);
                    NS_ENSURE_SUCCESS(res, res);
                    res = blue->GetFloatValue(nsIDOMCSSPrimitiveValue::CSS_NUMBER, &b);
                    NS_ENSURE_SUCCESS(res, res);
                    if (r >= BLACK_BG_RGB_TRIGGER &&
                            g >= BLACK_BG_RGB_TRIGGER &&
                            b >= BLACK_BG_RGB_TRIGGER)
                        aReturn.AssignLiteral("black");
                    else
                        aReturn.AssignLiteral("white");
                    return NS_OK;
                }
            }
        }
    }

    return NS_OK;
}

void
URL::GetHostname(nsAString& aHostname, ErrorResult& aRv) const
{
  aHostname.Truncate();
  nsContentUtils::GetHostOrIPv6WithBrackets(mURI, aHostname);
}

nsresult
nsXULContentUtils::GetTextForNode(nsIRDFNode* aNode, nsAString& aResult)
{
    if (! aNode) {
        aResult.Truncate();
        return NS_OK;
    }

    nsresult rv;

    // Literals are the most common, so try these first.
    nsCOMPtr<nsIRDFLiteral> literal = do_QueryInterface(aNode);
    if (literal) {
        const char16_t* p;
        rv = literal->GetValueConst(&p);
        if (NS_FAILED(rv)) return rv;

        aResult = p;
        return NS_OK;
    }

    nsCOMPtr<nsIRDFDate> dateLiteral = do_QueryInterface(aNode);
    if (dateLiteral) {
        PRTime value;
        rv = dateLiteral->GetValue(&value);
        if (NS_FAILED(rv)) return rv;

        nsAutoString str;
        rv = gFormat->FormatPRTime(nullptr /* nsILocale* locale */,
                                  kDateFormatShort,
                                  kTimeFormatSeconds,
                                  value,
                                  str);
        aResult.Assign(str);

        if (NS_FAILED(rv)) return rv;

        return NS_OK;
    }

    nsCOMPtr<nsIRDFInt> intLiteral = do_QueryInterface(aNode);
    if (intLiteral) {
        int32_t	value;
        rv = intLiteral->GetValue(&value);
        if (NS_FAILED(rv)) return rv;

        aResult.Truncate();
        nsAutoString intStr;
        intStr.AppendInt(value, 10);
        aResult.Append(intStr);
        return NS_OK;
    }


    nsCOMPtr<nsIRDFResource> resource = do_QueryInterface(aNode);
    if (resource) {
        const char* p;
        rv = resource->GetValueConst(&p);
        if (NS_FAILED(rv)) return rv;
        CopyUTF8toUTF16(p, aResult);
        return NS_OK;
    }

    NS_ERROR("not a resource or a literal");
    return NS_ERROR_UNEXPECTED;
}

// RFC 3454
//
// 1) Map -- For each character in the input, check if it has a mapping
// and, if so, replace it with its mapping. This is described in section 3.
//
// 2) Normalize -- Possibly normalize the result of step 1 using Unicode
// normalization. This is described in section 4.
//
// 3) Prohibit -- Check for any characters that are not allowed in the
// output. If any are found, return an error. This is described in section
// 5.
//
// 4) Check bidi -- Possibly check for right-to-left characters, and if any
// are found, make sure that the whole string satisfies the requirements
// for bidirectional strings. If the string does not satisfy the requirements
// for bidirectional strings, return an error. This is described in section 6.
//
// 5) Check unassigned code points -- If allowUnassigned is false, check for
// any unassigned Unicode points and if any are found return an error.
// This is described in section 7.
//
nsresult nsIDNService::stringPrep(const nsAString& in, nsAString& out,
                                  stringPrepFlag flag)
{
#ifdef IDNA2008
  return IDNA2008StringPrep(in, out, flag);
#else
  if (!mNamePrepHandle || !mNormalizer)
    return NS_ERROR_FAILURE;

  uint32_t ucs4Buf[kMaxDNSNodeLen + 1];
  uint32_t ucs4Len;
  nsresult rv = utf16ToUcs4(in, ucs4Buf, kMaxDNSNodeLen, &ucs4Len);
  NS_ENSURE_SUCCESS(rv, rv);

  // map
  idn_result_t idn_err;

  uint32_t namePrepBuf[kMaxDNSNodeLen * 3];   // map up to three characters
  idn_err = idn_nameprep_map(mNamePrepHandle, (const uint32_t *) ucs4Buf,
		                     (uint32_t *) namePrepBuf, kMaxDNSNodeLen * 3);
  NS_ENSURE_TRUE(idn_err == idn_success, NS_ERROR_FAILURE);

  nsAutoString namePrepStr;
  ucs4toUtf16(namePrepBuf, namePrepStr);
  if (namePrepStr.Length() >= kMaxDNSNodeLen)
    return NS_ERROR_FAILURE;

  // normalize
  nsAutoString normlizedStr;
  rv = mNormalizer->NormalizeUnicodeNFKC(namePrepStr, normlizedStr);
  if (normlizedStr.Length() >= kMaxDNSNodeLen)
    return NS_ERROR_FAILURE;

  // set the result string
  out.Assign(normlizedStr);

  if (flag == eStringPrepIgnoreErrors) {
    return NS_OK;
  }

  // prohibit
  const uint32_t *found = nullptr;
  idn_err = idn_nameprep_isprohibited(mNamePrepHandle,
                                      (const uint32_t *) ucs4Buf, &found);
  if (idn_err != idn_success || found) {
    rv = NS_ERROR_FAILURE;
  } else {
    // check bidi
    idn_err = idn_nameprep_isvalidbidi(mNamePrepHandle,
                                       (const uint32_t *) ucs4Buf, &found);
    if (idn_err != idn_success || found) {
      rv = NS_ERROR_FAILURE;
    } else  if (flag == eStringPrepForUI) {
      // check unassigned code points
      idn_err = idn_nameprep_isunassigned(mNamePrepHandle,
                                          (const uint32_t *) ucs4Buf, &found);
      if (idn_err != idn_success || found) {
        rv = NS_ERROR_FAILURE;
      }
    }
  }

  if (flag == eStringPrepForDNS && NS_FAILED(rv)) {
    out.Truncate();
  }

  return rv;
#endif
}

nsresult
nsHTMLEditor::CheckPositionedElementBGandFG(nsIDOMElement * aElement,
                                            nsAString & aReturn)
{
  // we are going to outline the positioned element and bring it to the
  // front to overlap any other element intersecting with it. But
  // first, let's see what's the background and foreground colors of the
  // positioned element.
  // if background-image computed value is 'none,
  //   If the background color is 'auto' and R G B values of the foreground are
  //       each above #d0, use a black background
  //   If the background color is 'auto' and at least one of R G B values of
  //       the foreground is below #d0, use a white background
  // Otherwise don't change background/foreground

  aReturn.Truncate();
  
  nsAutoString bgImageStr;
  nsresult res =
    mHTMLCSSUtils->GetComputedProperty(aElement, nsGkAtoms::background_image,
                                       bgImageStr);
  NS_ENSURE_SUCCESS(res, res);
  if (bgImageStr.EqualsLiteral("none")) {
    nsAutoString bgColorStr;
    res =
      mHTMLCSSUtils->GetComputedProperty(aElement, nsGkAtoms::backgroundColor,
                                         bgColorStr);
    NS_ENSURE_SUCCESS(res, res);
    if (bgColorStr.EqualsLiteral("transparent")) {
      nsRefPtr<nsComputedDOMStyle> cssDecl =
        mHTMLCSSUtils->GetComputedStyle(aElement);
      NS_ENSURE_STATE(cssDecl);

      // from these declarations, get the one we want and that one only
      ErrorResult error;
      nsRefPtr<dom::CSSValue> cssVal = cssDecl->GetPropertyCSSValue(NS_LITERAL_STRING("color"), error);
      NS_ENSURE_SUCCESS(error.ErrorCode(), error.ErrorCode());

      nsROCSSPrimitiveValue* val = cssVal->AsPrimitiveValue();
      NS_ENSURE_TRUE(val, NS_ERROR_FAILURE);

      if (nsIDOMCSSPrimitiveValue::CSS_RGBCOLOR == val->PrimitiveType()) {
        nsDOMCSSRGBColor* rgbVal = val->GetRGBColorValue(error);
        NS_ENSURE_SUCCESS(error.ErrorCode(), error.ErrorCode());
        float r = rgbVal->Red()->
          GetFloatValue(nsIDOMCSSPrimitiveValue::CSS_NUMBER, error);
        NS_ENSURE_SUCCESS(error.ErrorCode(), error.ErrorCode());
        float g = rgbVal->Green()->
          GetFloatValue(nsIDOMCSSPrimitiveValue::CSS_NUMBER, error);
        NS_ENSURE_SUCCESS(error.ErrorCode(), error.ErrorCode());
        float b = rgbVal->Blue()->
          GetFloatValue(nsIDOMCSSPrimitiveValue::CSS_NUMBER, error);
        NS_ENSURE_SUCCESS(error.ErrorCode(), error.ErrorCode());
        if (r >= BLACK_BG_RGB_TRIGGER &&
            g >= BLACK_BG_RGB_TRIGGER &&
            b >= BLACK_BG_RGB_TRIGGER)
          aReturn.AssignLiteral("black");
        else
          aReturn.AssignLiteral("white");
        return NS_OK;
      }
    }
  }

  return NS_OK;
}

void
nsAttrValue::ToString(nsAString& aResult) const
{
  MiscContainer* cont = nullptr;
  if (BaseType() == eOtherBase) {
    cont = GetMiscContainer();

    if (cont->GetString(aResult)) {
      return;
    }
  }

  switch(Type()) {
    case eString:
    {
      nsStringBuffer* str = static_cast<nsStringBuffer*>(GetPtr());
      if (str) {
        str->ToString(str->StorageSize()/sizeof(PRUnichar) - 1, aResult);
      }
      else {
        aResult.Truncate();
      }
      break;
    }
    case eAtom:
    {
      nsIAtom *atom = static_cast<nsIAtom*>(GetPtr());
      atom->ToString(aResult);

      break;
    }
    case eInteger:
    {
      nsAutoString intStr;
      intStr.AppendInt(GetIntegerValue());
      aResult = intStr;

      break;
    }
#ifdef DEBUG
    case eColor:
    {
      NS_NOTREACHED("color attribute without string data");
      aResult.Truncate();
      break;
    }
#endif
    case eEnum:
    {
      GetEnumString(aResult, false);
      break;
    }
    case ePercent:
    {
      nsAutoString intStr;
      intStr.AppendInt(cont ? cont->mValue.mPercent : GetIntInternal());
      aResult = intStr + NS_LITERAL_STRING("%");

      break;
    }
    case eCSSStyleRule:
    {
      aResult.Truncate();
      MiscContainer *container = GetMiscContainer();
      css::Declaration *decl =
        container->mValue.mCSSStyleRule->GetDeclaration();
      if (decl) {
        decl->ToString(aResult);
      }
      const_cast<nsAttrValue*>(this)->SetMiscAtomOrString(&aResult);

      break;
    }
    case eDoubleValue:
    {
      aResult.Truncate();
      aResult.AppendFloat(GetDoubleValue());
      break;
    }
    case eSVGAngle:
    {
      SVGAttrValueWrapper::ToString(GetMiscContainer()->mValue.mSVGAngle,
                                    aResult);
      break;
    }
    case eSVGIntegerPair:
    {
      SVGAttrValueWrapper::ToString(GetMiscContainer()->mValue.mSVGIntegerPair,
                                    aResult);
      break;
    }
    case eSVGLength:
    {
      SVGAttrValueWrapper::ToString(GetMiscContainer()->mValue.mSVGLength,
                                    aResult);
      break;
    }
    case eSVGLengthList:
    {
      SVGAttrValueWrapper::ToString(GetMiscContainer()->mValue.mSVGLengthList,
//.........这里部分代码省略.........