清除WKWebView的缓存

清除WKWebView的缓存，让H5页面一刷新就更新至最新的页面

直接上代码~！~~

要区分iOS9.0和8.0两种

- (void)deleteWebCache {

   
    if ([[UIDevice currentDevice].systemVersion floatValue] >= 9.0) {
        NSSet *websiteDataTypes
        = [NSSet setWithArray:@[
                                WKWebsiteDataTypeDiskCache,
                                //WKWebsiteDataTypeOfflineWebApplicationCache,
                                WKWebsiteDataTypeMemoryCache,
                                //WKWebsiteDataTypeLocalStorage,
                                //WKWebsiteDataTypeCookies,
                                //WKWebsiteDataTypeSessionStorage,
                                //WKWebsiteDataTypeIndexedDBDatabases,
                                //WKWebsiteDataTypeWebSQLDatabases
                                ]];
        //// All kinds of data
        //NSSet *websiteDataTypes = [WKWebsiteDataStore allWebsiteDataTypes];
        //// Date from
        NSDate *dateFrom = [NSDate dateWithTimeIntervalSince1970:0];
        //// Execute
        [[WKWebsiteDataStore defaultDataStore] removeDataOfTypes:websiteDataTypes modifiedSince:dateFrom completionHandler:^{
            // Done
        }];

    } else {
        
        NSString *libraryPath = [NSSearchPathForDirectoriesInDomains(NSLibraryDirectory, NSUserDomainMask, YES) objectAtIndex:0];
        NSString *cookiesFolderPath = [libraryPath stringByAppendingString:@"/Cookies"];
        NSError *errors;
        [[NSFileManager defaultManager] removeItemAtPath:cookiesFolderPath error:&errors];
        
    }
}