[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。
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。
程式撰寫起來會像下面這樣：
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.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。
為了方便起見也可以將之整理成擴充方法。
{
#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 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();
}
}
