[C#]Set Windows 7 Progress Bar's State

要在Win7設定Progressbar的運行狀態,可能是一般運行狀態,可能是暫停狀態,或是錯誤狀態。

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我們可以透過SendMessage發送PBM_SETSTATE訊息給ProgressBar,訊息的wParam依需求可帶入PBST_NORMAL、PBST_ERROR、與PBST_PAUSED,lParam部分則帶入0就可以了。

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程式撰寫起來會像下面這樣:

        #region Const
const int PBM_SETSTATE = 0x410;
const int PBST_PAUSE = 0x0003;
const int PBST_ERROR = 0x0002;
const int PBST_NORMAL = 0x0001;
#endregion


#region DllImport
[DllImport(“user32.dll”, CharSet = CharSet.Auto)]
internal static extern int SendMessage(IntPtr hWnd, int wMsg, int wParam, int lParam);
#endregion

#region Private Method
void SetPaused(ProgressBar progressBar)
{
SendMessage(progressBar.Handle, PBM_SETSTATE, PBST_PAUSE, 0);
}

void SetError(ProgressBar progressBar)
{
SendMessage(progressBar.Handle, PBM_SETSTATE, PBST_ERROR, 0);
}

void SetNormal(ProgressBar progressBar)
{
SendMessage(progressBar.Handle, PBM_SETSTATE, PBST_NORMAL, 0);
}
#endregion



這邊用此概念做個簡單的示意範例:


using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace WindowsFormsApplication3
{
public partial class Form1 : Form
{
#region Const
const int PBM_SETPOS = 0x402;
const int PBM_GETPOS = 0x0408;
const int PBM_SETSTATE = 0x410;
const int PBST_PAUSE = 0x0003;
const int PBST_ERROR = 0x0002;
const int PBST_NORMAL = 0x0001;
#endregion


#region DllImport
[DllImport(“user32.dll”, CharSet = CharSet.Auto)]
internal static extern int SendMessage(IntPtr hWnd, int wMsg, int wParam, int lParam);
#endregion

#region Private Method
void SetPaused(ProgressBar progressBar)
{
SendMessage(progressBar.Handle, PBM_SETSTATE, PBST_PAUSE, 0);
}

void SetError(ProgressBar progressBar)
{
SendMessage(progressBar.Handle, PBM_SETSTATE, PBST_ERROR, 0);
}

void SetNormal(ProgressBar progressBar)
{
SendMessage(progressBar.Handle, PBM_SETSTATE, PBST_NORMAL, 0);
}
#endregion

public Form1()
{
InitializeComponent();
}

private void trackBar1_Scroll(object sender, EventArgs e)
{
SendMessage(progressBar1.Handle, PBM_SETPOS, trackBar1.Value, 0);
}

private void button1_Click(object sender, EventArgs e)
{
SetNormal(progressBar1);
}

private void button2_Click(object sender, EventArgs e)
{
SetPaused(progressBar1);
}

private void button3_Click(object sender, EventArgs e)
{
SetError(progressBar1);
}
}
}



當按下不同狀態按鈕,ProgressBar會有不同的呈現。



image

image

image

為了方便起見也可以將之整理成擴充方法。

    public static class ProgressExtension
{
#region Const
const int PBM_SETSTATE = 0x410;
const int PBST_PAUSE = 0x0003;
const int PBST_ERROR = 0x0002;
const int PBST_NORMAL = 0x0001;
#endregion

#region DllImport
[DllImport(“user32.dll”, CharSet = CharSet.Auto)]
internal static extern int SendMessage(IntPtr hWnd, int wMsg, int wParam, int lParam);
#endregion

#region Public Method
public static void SetNormalState(this ProgressBar progressBar)
{
SendMessage(progressBar.Handle, PBM_SETSTATE, PBST_NORMAL, 0);
}

public static void SetPauseState(this ProgressBar progressBar)
{
SendMessage(progressBar.Handle, PBM_SETSTATE, PBST_PAUSE, 0);
}

public static void SetErrorState(this ProgressBar progressBar)
{
SendMessage(progressBar.Handle, PBM_SETSTATE, PBST_ERROR, 0);
}
#endregion
}

使用上會更為方便簡潔。

    public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}

private void trackBar1_Scroll(object sender, EventArgs e)
{
progressBar1.Value = trackBar1.Value;
}

private void button1_Click(object sender, EventArgs e)
{
progressBar1.SetNormalState();
}

private void button2_Click(object sender, EventArgs e)
{
progressBar1.SetPauseState();
}

private void button3_Click(object sender, EventArgs e)
{
progressBar1.SetErrorState();
}
}

Link


  • Windows 7 Progress Bars in .NET


  • PBM_SETSTATE message