如何使用整数标志

时间:2015-12-29 18:18:36

标签: c# enums

我正在尝试将整数变量设置为enum值的组合,enum为:

public enum WebBrowserDownloadControlFlags : uint
{
    DLIMAGES = 0x00000010,
    VIDEOS = 0x00000020,
    BGSOUNDS = 0x00000040,
    NO_SCRIPTS = 0x00000080,
    NO_JAVA = 0x00000100,
    NO_RUNACTIVEXCTLS = 0x00000200,
    NO_DLACTIVEXCTLS = 0x00000400,
    DOWNLOADONLY = 0x00000800,
    NO_FRAMEDOWNLOAD = 0x00001000,
    RESYNCHRONIZE = 0x00002000,
    PRAGMA_NO_CACHE = 0x00004000,
    NO_BEHAVIORS = 0x00008000,
    NO_METACHARSET = 0x00010000,
    URL_ENCODING_DISABLE_UTF8 = 0x00020000,
    URL_ENCODING_ENABLE_UTF8 = 0x00040000,
    NOFRAMES = 0x00080000,
    FORCEOFFLINE = 0x10000000,
    NO_CLIENTPULL = 0x20000000,
    SILENT = 0x40000000,
    OFFLINEIFNOTCONNECTED = 0x80000000,
    OFFLINE = OFFLINEIFNOTCONNECTED,
}

DownloadControlFlags是一个整数字段:

    public int DownloadControlFlags
    {
        get
        {
            return _downloadControlFlags;
        }
        set
        {
            if (_downloadControlFlags == value)
                return;

            _downloadControlFlags = value;
            IOleControl ctl = (IOleControl)ActiveXInstance;
            ctl.OnAmbientPropertyChange(DISPID_AMBIENT_DLCONTROL);
        }
    }

要设置此变量,我使用summation:

  webBrowser1.DownloadControlFlags = (int)WebBrowserDownloadControlFlags.DLIMAGES
             + (int)WebBrowserDownloadControlFlags.NOFRAMES
             + (int)WebBrowserDownloadControlFlags.NO_FRAMEDOWNLOAD
             + (int)WebBrowserDownloadControlFlags.NO_JAVA
             + (int)WebBrowserDownloadControlFlags.NO_DLACTIVEXCTLS
             + (int)WebBrowserDownloadControlFlags.NO_BEHAVIORS
             + (int)WebBrowserDownloadControlFlags.NO_RUNACTIVEXCTLS
        + (int)WebBrowserDownloadControlFlags.SILENT;

我不确定这是否是正确的方法,但它似乎有效。但现在我想检查变量是否包含特定值。对于正常enum,解决方案可以是此问题的答案How to check if any flags of a flag combination are set?,但我不确定在我的情况下是否可以使用相同的方式。

如何检查是否已设置特定标志?!例如,DownloadControlFlags是否包含WebBrowserDownloadControlFlags.NO_JAVA

1 个答案:

答案 0 :(得分:3)

  

对于正常的enum,解决方案可能是此问题How to check if any flags of a flag combination are set?的答案,但我不确定在我的情况下是否可以使用相同的方式。

你试过吗?

int flags = (int)WebBrowserDownloadControlFlags.DLIMAGES
         + (int)WebBrowserDownloadControlFlags.NOFRAMES
         + (int)WebBrowserDownloadControlFlags.NO_FRAMEDOWNLOAD
         + (int)WebBrowserDownloadControlFlags.NO_JAVA
         + (int)WebBrowserDownloadControlFlags.NO_DLACTIVEXCTLS
         + (int)WebBrowserDownloadControlFlags.NO_BEHAVIORS
         + (int)WebBrowserDownloadControlFlags.NO_RUNACTIVEXCTLS
         + (int)WebBrowserDownloadControlFlags.SILENT;

您可以使用Enum.HasFlag将其转换回枚举类型:

Console.WriteLine(((WebBrowserDownloadControlFlags)flags).HasFlag(WebBrowserDownloadControlFlags.NOFRAMES)); // true
Console.WriteLine(((WebBrowserDownloadControlFlags)flags).HasFlag(WebBrowserDownloadControlFlags.VIDEOS)); // false

或者您可以将要比较的枚举标记转换为int,然后进行逐位比较:

Console.WriteLine((flags & (int)WebBrowserDownloadControlFlags.NO_JAVA) != 0); // true
Console.WriteLine((flags & (int)WebBrowserDownloadControlFlags.VIDEOS) != 0); // false

但是你应该考虑一下你是否真的不希望将内部标志存储为WebBrowserDownloadControlFlags类型。没有理由尽早将其转换为int。你也可以这样做:

WebBrowserDownloadControlFlags flags = WebBrowserDownloadControlFlags.DLIMAGES
         | WebBrowserDownloadControlFlags.NOFRAMES
         | WebBrowserDownloadControlFlags.NO_FRAMEDOWNLOAD
         | WebBrowserDownloadControlFlags.NO_JAVA
         | WebBrowserDownloadControlFlags.NO_DLACTIVEXCTLS
         | WebBrowserDownloadControlFlags.NO_BEHAVIORS
         | WebBrowserDownloadControlFlags.NO_RUNACTIVEXCTLS
         | WebBrowserDownloadControlFlags.SILENT;

Console.WriteLine(flags.HasFlag(WebBrowserDownloadControlFlags.NOFRAMES)); // true
Console.WriteLine(flags.HasFlag(WebBrowserDownloadControlFlags.VIDEOS)); // false

Console.WriteLine((flags & WebBrowserDownloadControlFlags.NO_JAVA) != 0); // true
Console.WriteLine((flags & WebBrowserDownloadControlFlags.VIDEOS) != 0); // false

每当你真的需要一个int值时,你可以将整个事物转换成一个int:

Console.WriteLine((int)flags); // 1074304784