Question

为了使用WebClient而不是Chrome进行下载，我拦截了一个下载网址。然后我在使用访问者获取Cookie时遇到问题。我陷入的陷阱是我不明白访问者是异步运行的，因此只有30％的案例得到了正确的结果，过早地访问了收集的cookie。

当我搜索很长时间以寻找解决方案时，我想在此处粘贴我在演示代码中找到的那个。

Answer 1

这是我找到的代码。等待关键字是我失踪的重要部分：

class CookieCollector : ICookieVisitor
{
    private readonly TaskCompletionSource<List<Cookie>> _source = new TaskCompletionSource<List<Cookie>>();

    public bool Visit(Cookie cookie, int count, int total, ref bool deleteCookie)
    {
        _cookies.Add(cookie);

        if (count == (total - 1))
        {
            _source.SetResult(_cookies);
        }

    }

    // https://github.com/amaitland/CefSharp.MinimalExample/blob/ce6e579ad77dc92be94c0129b4a101f85e2fd75b/CefSharp.MinimalExample.WinForms/ListCookieVisitor.cs
    // CefSharp.MinimalExample.WinForms ListCookieVisitor 

    public Task<List<Cookie>> Task => _source.Task;

    public static string GetCookieHeader(List<Cookie> cookies)
    {

        StringBuilder cookieString = new StringBuilder();
        string delimiter = string.Empty;

        foreach (var cookie in cookies)
        {
            cookieString.Append(delimiter);
            cookieString.Append(cookie.Name);
            cookieString.Append('=');
            cookieString.Append(cookie.Value);
            delimiter = "; ";
        }

        return cookieString.ToString();
    }

    private readonly List<Cookie> _cookies = new List<Cookie>();
    public void Dispose()
    {
    }
}

// usage:
void foo()
{
    var cookieManager = Cef.GetGlobalCookieManager();
    var visitor = new CookieCollector();

    cookieManager.VisitUrlCookies(targetUrl, true, visitor);

    var cookies = await visitor.Task; // AWAIT !!!!!!!!!
    var cookieHeader = CookieCollector.GetCookieHeader(cookies);
}

如何使用CEFSharp收集所有cookie？

1 个答案: