How to turn Windows Proxy On/Off programmatically

Question

I need a code to turn Windows Proxy on or off. I tried:

WINHTTP_PROXY_INFO proxyInfo;
proxyInfo.dwAccessType = WINHTTP_ACCESS_TYPE_NO_PROXY;
proxyInfo.lpszProxy = new WCHAR[25] { 0 };
proxyInfo.lpszProxyBypass = new WCHAR[25] { 0 };
WinHttpSetDefaultProxyConfiguration(&proxyInfo)

but it does not turn the proxy off even with administrator privileges.

Is there a winapi code that can do that?

Answer 1

Turn Windows Proxy on,

#include <Windows.h>
#include <wininet.h>
#pragma comment(lib,"Wininet.lib")
void main()
{
 INTERNET_PER_CONN_OPTION options[2];
 INTERNET_PER_CONN_OPTION_LIST list{};
 list.dwSize = sizeof(list);
 list.dwOptionCount = 1;
 list.pOptions = options;
 options[0].dwOption = INTERNET_PER_CONN_FLAGS_UI;
 // Query the current value
 DWORD listSize = sizeof(list);
 InternetQueryOption(nullptr, INTERNET_OPTION_PER_CONNECTION_OPTION, &list, &listSize);
 options[0].Value.dwValue |= PROXY_TYPE_PROXY; 
 list.dwOptionCount = 2;
 options[1].dwOption = INTERNET_PER_CONN_PROXY_SERVER;
 WCHAR proxy[] = L"192.3.3.6";
 options[1].Value.pszValue = proxy;
 InternetSetOption(nullptr, INTERNET_OPTION_PER_CONNECTION_OPTION, &list, sizeof(list));
 InternetSetOption(nullptr, INTERNET_OPTION_SETTINGS_CHANGED, nullptr, 0);
}

Turn Windows Proxy off,

Modify this line:

options[0].Value.dwValue |= PROXY_TYPE_DIRECT; 

• Minimus Heximus: Thanks. options[0].Value.dwValue = PROXY_TYPE_DIRECT; works for turning off. And L"192.168.49.1:9099" can be used to set the port. But still I have problem. I don't want to change the default value of proxy when I turn it on?