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C++ Handle::isNullOrUndefined方法代码示例

本文整理汇总了C++中js::Handle::isNullOrUndefined方法的典型用法代码示例。如果您正苦于以下问题:C++ Handle::isNullOrUndefined方法的具体用法?C++ Handle::isNullOrUndefined怎么用?C++ Handle::isNullOrUndefined使用的例子?那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在js::Handle的用法示例。


在下文中一共展示了Handle::isNullOrUndefined方法的3个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的C++代码示例。

示例1: obj

// static
nsresult
IDBKeyRange::FromJSVal(JSContext* aCx,
                       JS::Handle<JS::Value> aVal,
                       IDBKeyRange** aKeyRange)
{
  nsRefPtr<IDBKeyRange> keyRange;

  if (aVal.isNullOrUndefined()) {
    // undefined and null returns no IDBKeyRange.
    keyRange.forget(aKeyRange);
    return NS_OK;
  }

  JS::Rooted<JSObject*> obj(aCx, aVal.isObject() ? &aVal.toObject() : nullptr);
  if (aVal.isPrimitive() || JS_IsArrayObject(aCx, obj) ||
      JS_ObjectIsDate(aCx, obj)) {
    // A valid key returns an 'only' IDBKeyRange.
    keyRange = new IDBKeyRange(nullptr, false, false, true);

    nsresult rv = GetKeyFromJSVal(aCx, aVal, keyRange->Lower());
    if (NS_FAILED(rv)) {
      return rv;
    }
  }
  else {
    MOZ_ASSERT(aVal.isObject());
    // An object is not permitted unless it's another IDBKeyRange.
    if (NS_FAILED(UNWRAP_OBJECT(IDBKeyRange, obj, keyRange))) {
      return NS_ERROR_DOM_INDEXEDDB_DATA_ERR;
    }
  }

  keyRange.forget(aKeyRange);
  return NS_OK;
}
开发者ID:JuannyWang,项目名称:gecko-dev,代码行数:36,代码来源:IDBKeyRange.cpp

示例2: obj

// static
nsresult
IDBKeyRange::FromJSVal(JSContext* aCx,
                       JS::Handle<JS::Value> aVal,
                       IDBKeyRange** aKeyRange)
{
  MOZ_ASSERT_IF(!aCx, aVal.isUndefined());

  RefPtr<IDBKeyRange> keyRange;

  if (aVal.isNullOrUndefined()) {
    // undefined and null returns no IDBKeyRange.
    keyRange.forget(aKeyRange);
    return NS_OK;
  }

  JS::Rooted<JSObject*> obj(aCx, aVal.isObject() ? &aVal.toObject() : nullptr);
  bool isValidKey = aVal.isPrimitive();
  if (!isValidKey) {
    js::ESClass cls;
    if (!js::GetBuiltinClass(aCx, obj, &cls)) {
      return NS_ERROR_UNEXPECTED;
    }
    isValidKey = cls == js::ESClass::Array || cls == js::ESClass::Date;
  }
  if (isValidKey) {
    // A valid key returns an 'only' IDBKeyRange.
    keyRange = new IDBKeyRange(nullptr, false, false, true);

    nsresult rv = GetKeyFromJSVal(aCx, aVal, keyRange->Lower());
    if (NS_FAILED(rv)) {
      return rv;
    }
  }
  else {
    MOZ_ASSERT(aVal.isObject());
    // An object is not permitted unless it's another IDBKeyRange.
    if (NS_FAILED(UNWRAP_OBJECT(IDBKeyRange, obj, keyRange))) {
      return NS_ERROR_DOM_INDEXEDDB_DATA_ERR;
    }
  }

  keyRange.forget(aKeyRange);
  return NS_OK;
}
开发者ID:bitwiseworks,项目名称:mozilla-os2,代码行数:45,代码来源:IDBKeyRange.cpp

示例3: GenerateWarning

NS_IMETHODIMP
WebGLContext::SetContextOptions(JSContext* aCx, JS::Handle<JS::Value> aOptions)
{
    if (aOptions.isNullOrUndefined() && mOptionsFrozen) {
        return NS_OK;
    }

    WebGLContextAttributes attributes;
    NS_ENSURE_TRUE(attributes.Init(aCx, aOptions), NS_ERROR_UNEXPECTED);

    WebGLContextOptions newOpts;

    newOpts.stencil = attributes.mStencil;
    newOpts.depth = attributes.mDepth;
    newOpts.premultipliedAlpha = attributes.mPremultipliedAlpha;
    newOpts.antialias = attributes.mAntialias;
    newOpts.preserveDrawingBuffer = attributes.mPreserveDrawingBuffer;
    if (attributes.mAlpha.WasPassed()) {
      newOpts.alpha = attributes.mAlpha.Value();
    }

    // enforce that if stencil is specified, we also give back depth
    newOpts.depth |= newOpts.stencil;

#if 0
    GenerateWarning("aaHint: %d stencil: %d depth: %d alpha: %d premult: %d preserve: %d\n",
               newOpts.antialias ? 1 : 0,
               newOpts.stencil ? 1 : 0,
               newOpts.depth ? 1 : 0,
               newOpts.alpha ? 1 : 0,
               newOpts.premultipliedAlpha ? 1 : 0,
               newOpts.preserveDrawingBuffer ? 1 : 0);
#endif

    if (mOptionsFrozen && newOpts != mOptions) {
        // Error if the options are already frozen, and the ones that were asked for
        // aren't the same as what they were originally.
        return NS_ERROR_FAILURE;
    }

    mOptions = newOpts;
    return NS_OK;
}
开发者ID:Sleepwalker2014,项目名称:gecko-dev,代码行数:43,代码来源:WebGLContext.cpp


注:本文中的js::Handle::isNullOrUndefined方法示例由纯净天空整理自Github/MSDocs等开源代码及文档管理平台,相关代码片段筛选自各路编程大神贡献的开源项目,源码版权归原作者所有,传播和使用请参考对应项目的License;未经允许,请勿转载。