Using API to shutdown a PC

[=?Utf-8?B?Z3JlYXRiYXJyaWVyODY=?=]

I've already got the code written but for some reason, when i click the
button, nothing occurs. Here is the code.

using System;
using System.Collecti ons.Generic;
using System.Componen tModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows. Forms;
using System.Runtime. InteropServices ;

[DllImport("adva pi32.dll",Entry Point="Initiate SystemShutdown" )]
public static extern bool InitiateSystemS hutdownA(string
lpMachineName, string lpMessage, int dwTimeout, int bForceAppsClose d, int
bRebootAfterShu tdown);

private void button1_Click(o bject sender, System.EventArg s e)
{
InitiateSystemS hutdownA(null,n ull, 30, 1, 1);
}

It compiles fine, but when i click button1, nothing happens. Any ideas?

[Michael Nemtsev, MVP]

Hello greatbarrier86,

Is your Button1 linked to OnClick event handler?

---
WBR,
Michael Nemtsev [.NET/C# MVP] :: blog: http://spaces.live.com/laflour

"The greatest danger for most of us is not that our aim is too high and we
miss it, but that it is too low and we reach it" (c) Michelangelo
gI've already got the code written but for some reason, when i click
gthe button, nothing occurs. Here is the code.
g>
gusing System;
gusing System.Collecti ons.Generic;
gusing System.Componen tModel;
gusing System.Data;
gusing System.Drawing;
gusing System.Text;
gusing System.Windows. Forms;
gusing System.Runtime. InteropServices ;
g[DllImport("adva pi32.dll",Entry Point="Initiate SystemShutdown" )]
gpublic static extern bool InitiateSystemS hutdownA(string
glpMachineName, string lpMessage, int dwTimeout, int bForceAppsClose d,
gint
gbRebootAfterSh utdown);
g>
gprivate void button1_Click(o bject sender, System.EventArg s e)
g{
gInitiateSystem ShutdownA(null, null, 30, 1, 1);
g}
gIt compiles fine, but when i click button1, nothing happens. Any
gideas?
g>

[=?Utf-8?B?Z3JlYXRiYXJyaWVyODY=?=]

Sorry. i am somewhat of a noob...how do i figure that out?

"Michael Nemtsev" <Michael Nemtsev>, "MVP" wrote:

Hello greatbarrier86,

Is your Button1 linked to OnClick event handler?

---
WBR,
Michael Nemtsev [.NET/C# MVP] :: blog: http://spaces.live.com/laflour

"The greatest danger for most of us is not that our aim is too high and we
miss it, but that it is too low and we reach it" (c) Michelangelo
gI've already got the code written but for some reason, when i click
gthe button, nothing occurs. Here is the code.
g>
gusing System;
gusing System.Collecti ons.Generic;
gusing System.Componen tModel;
gusing System.Data;
gusing System.Drawing;
gusing System.Text;
gusing System.Windows. Forms;
gusing System.Runtime. InteropServices ;
g[DllImport("adva pi32.dll",Entry Point="Initiate SystemShutdown" )]
gpublic static extern bool InitiateSystemS hutdownA(string
glpMachineName, string lpMessage, int dwTimeout, int bForceAppsClose d,
gint
gbRebootAfterSh utdown);
g>
gprivate void button1_Click(o bject sender, System.EventArg s e)
g{
gInitiateSystem ShutdownA(null, null, 30, 1, 1);
g}
gIt compiles fine, but when i click button1, nothing happens. Any
gideas?
g>

[Peter Duniho]

greatbarrier86 wrote:

"Michael Nemtsev" <Michael Nemtsev>, "MVP" wrote:

>Hello greatbarrier86,

Is your Button1 linked to OnClick event handler?

Sorry. i am somewhat of a noob...how do i figure that out?

Well, one way would be to set a breakpoint on the line of code inside
the method, then run your program and click the button.

If it's hooked up correctly, you'll hit the breakpoint.

IMHO, almost every line of code you write, you should step through it in
the debugger at least once. But especially if the code doesn't seem to
be working, the very first step would be to use the debugger to see if
it's being executed at all, and if it is, whether the code is doing what
you think (including returning the value you think it should).

Only once you have confirmed all of that should you worry about what
else might be wrong.

If you don't hit the breakpoint, then one way to ensure that it's hooked
up correctly would be to, in the VS designer, go to your form with the
button, select the button, then click on the lightning-bolt icon in the
properties window to display the events. Find the Click event and see
if that method is listed as the assigned handler.

If it's not, you should be able to click on the arrow in the field, find
the method you wrote, and select it as the handler.

Pete

[Willy Denoyette [MVP]]

"greatbarrier86 " <gr************ @discussions.mi crosoft.comwrot e in message
news:E3******** *************** ***********@mic rosoft.com...

I've already got the code written but for some reason, when i click the
button, nothing occurs. Here is the code.

using System;
using System.Collecti ons.Generic;
using System.Componen tModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows. Forms;
using System.Runtime. InteropServices ;

[DllImport("adva pi32.dll",Entry Point="Initiate SystemShutdown" )]
public static extern bool InitiateSystemS hutdownA(string
lpMachineName, string lpMessage, int dwTimeout, int bForceAppsClose d, int
bRebootAfterShu tdown);

private void button1_Click(o bject sender, System.EventArg s e)
{
InitiateSystemS hutdownA(null,n ull, 30, 1, 1);
}

It compiles fine, but when i click button1, nothing happens. Any ideas?

How do you know the call succeeded when you don't check the return value of
the API call?

Willy.

[=?Utf-8?B?Z3JlYXRiYXJyaWVyODY=?=]

Heh...like i said, i'm a noob :)

How do i check the return value?

"Willy Denoyette [MVP]" wrote:

"greatbarrier86 " <gr************ @discussions.mi crosoft.comwrot e in message
news:E3******** *************** ***********@mic rosoft.com...

I've already got the code written but for some reason, when i click the
button, nothing occurs. Here is the code.

using System;
using System.Collecti ons.Generic;
using System.Componen tModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows. Forms;
using System.Runtime. InteropServices ;

[DllImport("adva pi32.dll",Entry Point="Initiate SystemShutdown" )]
public static extern bool InitiateSystemS hutdownA(string
lpMachineName, string lpMessage, int dwTimeout, int bForceAppsClose d, int
bRebootAfterShu tdown);

private void button1_Click(o bject sender, System.EventArg s e)
{
InitiateSystemS hutdownA(null,n ull, 30, 1, 1);
}

It compiles fine, but when i click button1, nothing happens. Any ideas?

How do you know the call succeeded when you don't check the return value of
the API call?

Willy.

[Willy Denoyette [MVP]]

1) Change the DllImport declaration such that it returns an int value like:
public static extern int InitiateSystemS hutdownA(string ....

assign the return value to a variable like this:
int ret = InitiateSystemS hutdownA(null,n ull, 30, 1, 1);

2) Make sure the GetLastError returns something meaningful, by setting the
SetLastError to true.
[DllImport("adva pi32.dll",Entry Point="Initiate SystemShutdown" ,SetLastError=t rue)]

3) Check what "InitiateSystem Shutdown" can possibly return (in MSDN) and
take appropriate actions when the return is an error value.

if(ret == 0)
{
// Failed, most (but not all) Win32 API's return 0 on failure
// Call Marshall.GetLas tWin32Error to get the Win32 error code
}
else
// success.

Note that your code will most probably return error code 5, which means
"Access Denied". The reason for this is that you need to enable the
SE_SHUTDOWN_NAM E privileges. This again has to be done using native API
calls as this is not covered by the Framework classes.

That said, calling into Win32 through PInvoke is not something you should
start without reading the API description in the docs.

Willy.


"greatbarrier86 " <gr************ @discussions.mi crosoft.comwrot e in message
news:A8******** *************** ***********@mic rosoft.com...

Heh...like i said, i'm a noob :)

How do i check the return value?

"Willy Denoyette [MVP]" wrote:

>"greatbarrier8 6" <gr************ @discussions.mi crosoft.comwrot e in
message
news:E3******* *************** ************@mi crosoft.com...

I've already got the code written but for some reason, when i click the
button, nothing occurs. Here is the code.

using System;
using System.Collecti ons.Generic;
using System.Componen tModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows. Forms;
using System.Runtime. InteropServices ;

[DllImport("adva pi32.dll",Entry Point="Initiate SystemShutdown" )]
public static extern bool InitiateSystemS hutdownA(string
lpMachineName, string lpMessage, int dwTimeout, int bForceAppsClose d,
int
bRebootAfterShu tdown);

private void button1_Click(o bject sender, System.EventArg s e)
{
InitiateSystemS hutdownA(null,n ull, 30, 1, 1);
}

It compiles fine, but when i click button1, nothing happens. Any ideas?

How do you know the call succeeded when you don't check the return value
of
the API call?

Willy.

[=?Utf-8?B?Z3JlYXRiYXJyaWVyODY=?=]

Willy,

Thank you for all your help. It turned out that it failed. Can you explain
to me a little more about the SE_SHUTDOWN_NAM E privilege? Or at least how to
give that thread that privilege?

"Willy Denoyette [MVP]" wrote:

1) Change the DllImport declaration such that it returns an int value like:
public static extern int InitiateSystemS hutdownA(string ....

assign the return value to a variable like this:
int ret = InitiateSystemS hutdownA(null,n ull, 30, 1, 1);

2) Make sure the GetLastError returns something meaningful, by setting the
SetLastError to true.
[DllImport("adva pi32.dll",Entry Point="Initiate SystemShutdown" ,SetLastError=t rue)]

3) Check what "InitiateSystem Shutdown" can possibly return (in MSDN) and
take appropriate actions when the return is an error value.

if(ret == 0)
{
// Failed, most (but not all) Win32 API's return 0 on failure
// Call Marshall.GetLas tWin32Error to get the Win32 error code
}
else
// success.

Note that your code will most probably return error code 5, which means
"Access Denied". The reason for this is that you need to enable the
SE_SHUTDOWN_NAM E privileges. This again has to be done using native API
calls as this is not covered by the Framework classes.

That said, calling into Win32 through PInvoke is not something you should
start without reading the API description in the docs.

Willy.


"greatbarrier86 " <gr************ @discussions.mi crosoft.comwrot e in message
news:A8******** *************** ***********@mic rosoft.com...

Heh...like i said, i'm a noob :)

How do i check the return value?

"Willy Denoyette [MVP]" wrote:

"greatbarrier86 " <gr************ @discussions.mi crosoft.comwrot e in
message
news:E3******** *************** ***********@mic rosoft.com...
I've already got the code written but for some reason, when i click the
button, nothing occurs. Here is the code.

using System;
using System.Collecti ons.Generic;
using System.Componen tModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows. Forms;
using System.Runtime. InteropServices ;

[DllImport("adva pi32.dll",Entry Point="Initiate SystemShutdown" )]
public static extern bool InitiateSystemS hutdownA(string
lpMachineName, string lpMessage, int dwTimeout, int bForceAppsClose d,
int
bRebootAfterShu tdown);

private void button1_Click(o bject sender, System.EventArg s e)
{
InitiateSystemS hutdownA(null,n ull, 30, 1, 1);
}

It compiles fine, but when i click button1, nothing happens. Any ideas?

How do you know the call succeeded when you don't check the return value
of
the API call?

Willy.

[=?Utf-8?B?Z3JlYXRiYXJyaWVyODY=?=]

Willy, I used the GetLastWin32Err or and it returned "The Parameter is
Incorrect." I'm a little confused.

"Willy Denoyette [MVP]" wrote:

1) Change the DllImport declaration such that it returns an int value like:
public static extern int InitiateSystemS hutdownA(string ....

assign the return value to a variable like this:
int ret = InitiateSystemS hutdownA(null,n ull, 30, 1, 1);

2) Make sure the GetLastError returns something meaningful, by setting the
SetLastError to true.
[DllImport("adva pi32.dll",Entry Point="Initiate SystemShutdown" ,SetLastError=t rue)]

3) Check what "InitiateSystem Shutdown" can possibly return (in MSDN) and
take appropriate actions when the return is an error value.

if(ret == 0)
{
// Failed, most (but not all) Win32 API's return 0 on failure
// Call Marshall.GetLas tWin32Error to get the Win32 error code
}
else
// success.

Note that your code will most probably return error code 5, which means
"Access Denied". The reason for this is that you need to enable the
SE_SHUTDOWN_NAM E privileges. This again has to be done using native API
calls as this is not covered by the Framework classes.

That said, calling into Win32 through PInvoke is not something you should
start without reading the API description in the docs.

Willy.


"greatbarrier86 " <gr************ @discussions.mi crosoft.comwrot e in message
news:A8******** *************** ***********@mic rosoft.com...

Heh...like i said, i'm a noob :)

How do i check the return value?

"Willy Denoyette [MVP]" wrote:

"greatbarrier86 " <gr************ @discussions.mi crosoft.comwrot e in
message
news:E3******** *************** ***********@mic rosoft.com...
I've already got the code written but for some reason, when i click the
button, nothing occurs. Here is the code.

using System;
using System.Collecti ons.Generic;
using System.Componen tModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows. Forms;
using System.Runtime. InteropServices ;

[DllImport("adva pi32.dll",Entry Point="Initiate SystemShutdown" )]
public static extern bool InitiateSystemS hutdownA(string
lpMachineName, string lpMessage, int dwTimeout, int bForceAppsClose d,
int
bRebootAfterShu tdown);

private void button1_Click(o bject sender, System.EventArg s e)
{
InitiateSystemS hutdownA(null,n ull, 30, 1, 1);
}

It compiles fine, but when i click button1, nothing happens. Any ideas?

How do you know the call succeeded when you don't check the return value
of
the API call?

Willy.

[Andrew P.]

I haven't read the whole list of messages so I'm not sure if anyone
suggested that you use the System.Manageme nt assembly. Just yesterday I
wrote the code for this:
http://www.geekpedia.com/code36_Shut...ng-Csharp.html

The reason your original code doesn't work is that it doesn't get the
required privileges. My code does that.

Let me know if you have questions.

Andrew

"greatbarrier86 " <gr************ @discussions.mi crosoft.comwrot e in message
news:E3******** *************** ***********@mic rosoft.com...

I've already got the code written but for some reason, when i click the
button, nothing occurs. Here is the code.

using System;
using System.Collecti ons.Generic;
using System.Componen tModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows. Forms;
using System.Runtime. InteropServices ;

[DllImport("adva pi32.dll",Entry Point="Initiate SystemShutdown" )]
public static extern bool InitiateSystemS hutdownA(string
lpMachineName, string lpMessage, int dwTimeout, int bForceAppsClose d, int
bRebootAfterShu tdown);

private void button1_Click(o bject sender, System.EventArg s e)
{
InitiateSystemS hutdownA(null,n ull, 30, 1, 1);
}

It compiles fine, but when i click button1, nothing happens. Any ideas?