页面有变化会导致,从代码上看:
if (sameDocumentNavigation)
loadSameDocumentItem(item);
else
loadDifferentDocumentItem(item, loadType);
而loadDifferentDocumentItem函数
switch (loadType) {
case FrameLoadTypeReload:
case FrameLoadTypeReloadFromOrigin:
request.setCachePolicy(ReloadIgnoringCacheData);
break;
case FrameLoadTypeBack:
case FrameLoadTypeBackWMLDeckNotAccessible:
case FrameLoadTypeForward:
case FrameLoadTypeIndexedBackForward:
// If the first load within a frame is a navigation within a back/forward list that was attached
// without any of the items being loaded then we should use the default caching policy (<rdar://problem/8131355>).
if (m_stateMachine.committedFirstRealDocumentLoad() && !itemURL.protocolIs("https"))
request.setCachePolicy(ReturnCacheDataElseLoad);
break;
case FrameLoadTypeStandard:
case FrameLoadTypeRedirectWithLockedBackForwardList:
break;
case FrameLoadTypeSame:
default:
ASSERT_NOT_REACHED();
}
action = NavigationAction(itemOriginalURL, loadType, false);
}
if (!addedExtraFields)
addExtraFieldsToRequest(request, m_loadType, true, formData);
loadWithNavigationAction(request, action, false, loadType, 0);
而最后一个函数 无论从不从cache拿数据 都会刷新