C# 設置ie代理

        /// <summary>
        /// 設置代理的Api
        /// </summary>
        /// <returns></returns>
        [DllImport("wininet.dll", SetLastError = true)]
        private static extern bool InternetSetOption(IntPtr hInternet, int dwOption, IntPtr lpBuffer, int lpdwBufferLength);
        /// <summary>
        /// 代理IP以及端口號
        /// </summary>
        /// <param name="strProxy"></param>
        private void RefreshIESettings(string strProxy)
        {
            const int INTERNET_OPTION_PROXY = 38;
            const int INTERNET_OPEN_TYPE_PROXY = 3;

            Struct_INTERNET_PROXY_INFO struct_IPI;

            struct_IPI.dwAccessType = INTERNET_OPEN_TYPE_PROXY;
            struct_IPI.proxy = Marshal.StringToHGlobalAnsi(strProxy);
            struct_IPI.proxyBypass = Marshal.StringToHGlobalAnsi("local");

            IntPtr intptrStruct = Marshal.AllocCoTaskMem(Marshal.SizeOf(struct_IPI));

            Marshal.StructureToPtr(struct_IPI, intptrStruct, true);

            bool iReturn = InternetSetOption(IntPtr.Zero, INTERNET_OPTION_PROXY, intptrStruct, Marshal.SizeOf(struct_IPI));
        }
        /// <summary>
        /// 代理結構體
        /// </summary>
        public struct Struct_INTERNET_PROXY_INFO
        {
            public int dwAccessType;
            public IntPtr proxy;//IP以及端口號
            public IntPtr proxyBypass;
        };

調用RefreshIESettings（ip：端口）