用戶如何在運行時在 winforms 中調整控件的大小

Question

假設我有一個圖片框。

現在我想要的是用戶應該能夠隨意調整圖片框的大小。 但是，我不知道如何開始這件事。 我已經搜索過互聯網，但信息很少。

至少有人可以指導我從哪里開始嗎？

Answer 1

這很容易做到，Windows 中的每個窗口都有天生的可調整大小的能力。 它只是為 PictureBox 關閉，您可以通過偵聽WM_NCHITTEST 消息將其重新打開。 您只需告訴 Windows 光標位於窗口的一角，您就可以免費獲得其他一切。 您還需要繪制一個把手，以便用戶清楚拖動角將調整框的大小。

向您的項目添加一個新類並粘貼如下所示的代碼。 構建+構建。 您將在工具箱頂部獲得一個新控件，將其放在表單上。 設置 Image 屬性，您就可以嘗試了。

using System;
using System.Drawing;
using System.Windows.Forms;

class SizeablePictureBox : PictureBox {
    public SizeablePictureBox() {
        this.ResizeRedraw = true;
    }
    protected override void OnPaint(PaintEventArgs e) {
        base.OnPaint(e);
        var rc = new Rectangle(this.ClientSize.Width - grab, this.ClientSize.Height - grab, grab, grab);
        ControlPaint.DrawSizeGrip(e.Graphics, this.BackColor, rc); 
    }
    protected override void WndProc(ref Message m) {
        base.WndProc(ref m);
        if (m.Msg == 0x84) {  // Trap WM_NCHITTEST
            var pos = this.PointToClient(new Point(m.LParam.ToInt32()));
            if (pos.X >= this.ClientSize.Width - grab && pos.Y >= this.ClientSize.Height - grab)
                m.Result = new IntPtr(17);  // HT_BOTTOMRIGHT
        }
    }
    private const int grab = 16;
}

另一種免費調整大小的非常便宜的方法是給控件一個可調整大小的邊框。 這適用於所有角落和邊緣。 將此代碼粘貼到類中（您不再需要 WndProc）：

protected override CreateParams CreateParams {
    get {
        var cp = base.CreateParams;
        cp.Style |= 0x840000;  // Turn on WS_BORDER + WS_THICKFRAME
        return cp;
    }
}

Answer 2

這是一篇文章

http://www.codeproject.com/Articles/20716/Allow-the-User-to-Resize-Controls-at-Runtime

這應該對你有所幫助，因為它在 vb 中是一個 C# 翻譯

using System;
using System.Collections;
using System.Collections.Generic;
using System.Data;
using System.Diagnostics;
public class Form1
{


    ResizeableControl rc;

    private void Form1_Load(System.Object sender, System.EventArgs e)
    {
        rc = new ResizeableControl(pbDemo);

    }
    public Form1()
    {
        Load += Form1_Load;
    }

}

和調整大小功能

using System;
using System.Collections;
using System.Collections.Generic;
using System.Data;
using System.Diagnostics;
public class ResizeableControl
{

    private Control withEventsField_mControl;
    private Control mControl {
        get { return withEventsField_mControl; }
        set {
            if (withEventsField_mControl != null) {
                withEventsField_mControl.MouseDown -= mControl_MouseDown;
                withEventsField_mControl.MouseUp -= mControl_MouseUp;
                withEventsField_mControl.MouseMove -= mControl_MouseMove;
                withEventsField_mControl.MouseLeave -= mControl_MouseLeave;
            }
            withEventsField_mControl = value;
            if (withEventsField_mControl != null) {
                withEventsField_mControl.MouseDown += mControl_MouseDown;
                withEventsField_mControl.MouseUp += mControl_MouseUp;
                withEventsField_mControl.MouseMove += mControl_MouseMove;
                withEventsField_mControl.MouseLeave += mControl_MouseLeave;
            }
        }
    }
    private bool mMouseDown = false;
    private EdgeEnum mEdge = EdgeEnum.None;
    private int mWidth = 4;

    private bool mOutlineDrawn = false;
    private enum EdgeEnum
    {
        None,
        Right,
        Left,
        Top,
        Bottom,
        TopLeft
    }

    public ResizeableControl(Control Control)
    {
        mControl = Control;
    }


    private void mControl_MouseDown(object sender, System.Windows.Forms.MouseEventArgs e)
    {
        if (e.Button == System.Windows.Forms.MouseButtons.Left) {
            mMouseDown = true;
        }
    }


    private void mControl_MouseUp(object sender, System.Windows.Forms.MouseEventArgs e)
    {
        mMouseDown = false;
    }


    private void mControl_MouseMove(object sender, System.Windows.Forms.MouseEventArgs e)
    {
        Control c = (Control)sender;
        Graphics g = c.CreateGraphics;
        switch (mEdge) {
            case EdgeEnum.TopLeft:
                g.FillRectangle(Brushes.Fuchsia, 0, 0, mWidth * 4, mWidth * 4);
                mOutlineDrawn = true;
                break;
            case EdgeEnum.Left:
                g.FillRectangle(Brushes.Fuchsia, 0, 0, mWidth, c.Height);
                mOutlineDrawn = true;
                break;
            case EdgeEnum.Right:
                g.FillRectangle(Brushes.Fuchsia, c.Width - mWidth, 0, c.Width, c.Height);
                mOutlineDrawn = true;
                break;
            case EdgeEnum.Top:
                g.FillRectangle(Brushes.Fuchsia, 0, 0, c.Width, mWidth);
                mOutlineDrawn = true;
                break;
            case EdgeEnum.Bottom:
                g.FillRectangle(Brushes.Fuchsia, 0, c.Height - mWidth, c.Width, mWidth);
                mOutlineDrawn = true;
                break;
            case EdgeEnum.None:
                if (mOutlineDrawn) {
                    c.Refresh();
                    mOutlineDrawn = false;
                }
                break;
        }

        if (mMouseDown & mEdge != EdgeEnum.None) {
            c.SuspendLayout();
            switch (mEdge) {
                case EdgeEnum.TopLeft:
                    c.SetBounds(c.Left + e.X, c.Top + e.Y, c.Width, c.Height);
                    break;
                case EdgeEnum.Left:
                    c.SetBounds(c.Left + e.X, c.Top, c.Width - e.X, c.Height);
                    break;
                case EdgeEnum.Right:
                    c.SetBounds(c.Left, c.Top, c.Width - (c.Width - e.X), c.Height);
                    break;
                case EdgeEnum.Top:
                    c.SetBounds(c.Left, c.Top + e.Y, c.Width, c.Height - e.Y);
                    break;
                case EdgeEnum.Bottom:
                    c.SetBounds(c.Left, c.Top, c.Width, c.Height - (c.Height - e.Y));
                    break;
            }
            c.ResumeLayout();
        } else {
            switch (true) {
                case e.X <= (mWidth * 4) & e.Y <= (mWidth * 4):
                    //top left corner
                    c.Cursor = Cursors.SizeAll;
                    mEdge = EdgeEnum.TopLeft;
                    break;
                case e.X <= mWidth:
                    //left edge
                    c.Cursor = Cursors.VSplit;
                    mEdge = EdgeEnum.Left;
                    break;
                case e.X > c.Width - (mWidth + 1):
                    //right edge
                    c.Cursor = Cursors.VSplit;
                    mEdge = EdgeEnum.Right;
                    break;
                case e.Y <= mWidth:
                    //top edge
                    c.Cursor = Cursors.HSplit;
                    mEdge = EdgeEnum.Top;
                    break;
                case e.Y > c.Height - (mWidth + 1):
                    //bottom edge
                    c.Cursor = Cursors.HSplit;
                    mEdge = EdgeEnum.Bottom;
                    break;
                default:
                    //no edge
                    c.Cursor = Cursors.Default;
                    mEdge = EdgeEnum.None;
                    break;
            }
        }
    }


    private void mControl_MouseLeave(object sender, System.EventArgs e)
    {
        Control c = (Control)sender;
        mEdge = EdgeEnum.None;
        c.Refresh();
    }

}

Answer 3

通過使用本文中的ControlMoverOrResizer 類，您只需一行代碼即可在運行時實現可移動和可調整大小的控件！ ：） 例子：

ControlMoverOrResizer.Init(button1);

現在 button1 是一個可移動和可調整大小的控件！

Answer 4

創建一個新的 c# winform 應用程序並粘貼：

幫到你的時候別忘了說聲謝謝...

http://www.codeproject.com/script/Articles/ArticleVersion.aspx?aid=743923&av=1095793&msg=4778687

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace WindowsFormsApplication1
  {
 public partial class MyForm : Form
  {
    //Public Declaration:
    double rW = 0;
    double rH = 0;

    int fH = 0;
    int fW = 0;


    // @ Form Initialization
    public MyForm()
    {
        InitializeComponent();
        this.Resize += MyForm_Resize; // handles resize routine
        this.tabControl1.Dock = DockStyle.None;

    }


    private void MyForm_Resize(object sender, EventArgs e)
    {
        rResize(this,true); //Call the routine

    }

    private void rResize(Control t, bool hasTabs) // Routine to Auto resize the control
    {

        // this will return to normal default size when 1 of the conditions is met

        string[] s = null;

        if (this.Width < fW || this.Height < fH)
        {

            this.Width = (int)fW;
            this.Height = (int)fH;

            return;
        }

        foreach (Control c in t.Controls)
        {
            // Option 1:
            double rRW = (t.Width > rW ? t.Width / (rW) : rW / t.Width);
            double rRH = (t.Height > rH ? t.Height / (rH) : rH / t.Height);

            // Option 2:
            //  double rRW = t.Width / rW;
            //  double rRH = t.Height / rH;

            s = c.Tag.ToString().Split('/');
            if (c.Name == s[0].ToString())
            {
                //Use integer casting
                c.Width = (int)(Convert.ToInt32(s[3]) * rRW);
                c.Height = (int)(Convert.ToInt32(s[4]) * rRH);
                c.Left = (int)(Convert.ToInt32(s[1]) * rRW);
                c.Top = (int)(Convert.ToInt32(s[2]) * rRH);
            }
            if (hasTabs)
            {
                if (c.GetType() == typeof(TabControl))
                {

                    foreach (Control f in c.Controls)
                    {
                        foreach (Control j in f.Controls) //tabpage
                        {
                            s = j.Tag.ToString().Split('/');

                            if (j.Name == s[0].ToString())
                            {

                                j.Width = (int)(Convert.ToInt32(s[3]) * rRW);
                                j.Height = (int)(Convert.ToInt32(s[4]) * rRH);
                                j.Left = (int)(Convert.ToInt32(s[1]) * rRW);
                                j.Top = (int)(Convert.ToInt32(s[2]) * rRH);
                            }
                        }
                    }
                }
            }

        }
    }

    // @ Form Load Event
    private void MyForm_Load(object sender, EventArgs e)
    {


        // Put values in the variables

        rW = this.Width;
        rH = this.Height;

        fW = this.Width;
        fH = this.Height;


        // Loop through the controls inside the  form i.e. Tabcontrol Container
        foreach (Control c in this.Controls)
        {
            c.Tag = c.Name + "/" + c.Left + "/" + c.Top + "/" + c.Width + "/" + c.Height;

            // c.Anchor = (AnchorStyles.Right |  AnchorStyles.Left ); 

            if (c.GetType() == typeof(TabControl))
            {

                foreach (Control f in c.Controls)
                {

                    foreach (Control j in f.Controls) //tabpage
                    {
                        j.Tag = j.Name + "/" + j.Left + "/" + j.Top + "/" + j.Width + "/" + j.Height;
                    }
                }
            }
        }
    }
}
}

問候， Kix46

Answer 5

namespace utils
{
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.IO;
using System.Data;
using System.Globalization;
using System.Xml;
using System.Text.RegularExpressions;
using System.Drawing;
public static class Helper
{
    public const int WM_NCLBUTTONDOWN = 0xA1;
    public const int HTCAPTION = 2;
    public static int WS_THICKFRAME = 0x00040000;
    public static int GWL_STYLE = -16;
    public static int GWL_EXSTYLE = -20;
    public static int WS_EX_LAYERED = 0x00080000;
    public const int WS_RESIZABLE = 0x840000; //WS_BORDER + WS_THICKFRAME

    [System.Runtime.InteropServices.DllImport("user32.dll")]
    static extern IntPtr GetSystemMenu(IntPtr hWnd, bool bRevert);

    [System.Runtime.InteropServices.DllImport("user32.dll")]
    static extern bool AppendMenu(IntPtr hMenu, uint uFlags, uint uIDNewItem, string lpNewItem);

    [System.Runtime.InteropServices.DllImport("user32.dll")]
    public static extern int SetWindowLong(IntPtr hWnd, int nIndex, int dwNewLong);

    [System.Runtime.InteropServices.DllImport("user32.dll")]
    public static extern int GetWindowLong(IntPtr hWnd, int nIndex);

    [System.Runtime.InteropServices.DllImport("user32.dll")]
    public static extern int
    SetLayeredWindowAttributes(IntPtr Handle, int Clr, byte transparency, int clrkey);

    [System.Runtime.InteropServices.DllImport("shell32.dll")]
    public static extern IntPtr ShellExecute(IntPtr hwnd, string lpOperation, string lpFile, string lpParameters, string lpDirectory, int nShowCmd);

    [return: System.Runtime.InteropServices.MarshalAs(System.Runtime.InteropServices.UnmanagedType.Bool)]
    [System.Runtime.InteropServices.DllImport("user32.dll", SetLastError = true)]
    public static extern bool PostMessage(IntPtr hWnd, int Msg, IntPtr wParam, IntPtr lParam);

    [System.Runtime.InteropServices.DllImport("kernel32.dll")]
    public static extern uint GetCurrentThreadId();
    public static string ProcessException(this Exception ex)
    {
        StringBuilder strBuild = new StringBuilder(5000);
        Exception inner = ex;
        Enumerable.Range(0, 30).All(x =>
        {
            if (x == 0) strBuild.Append("########## Exception begin on thread id : " + GetCurrentThreadId().ToString() + " @ :" + DateTime.Now.ToString() + " ##########\n");
            strBuild.Append("---------------------[" + x.ToString() + "]---------------------\n");
            strBuild.Append("Message : " + inner.Message + "\nStack Trace : " + inner.StackTrace + "\n");
            strBuild.Append("---------------------[" + x.ToString() + "]---------------------\n");
            inner = inner.InnerException;
            if (inner == null)
            {
                strBuild.Append("########## Exception End on thread id : " + GetCurrentThreadId().ToString() + " @ :" + DateTime.Now.ToString() + " ##########\n\n");
                return false;
            }
            return true;
        });
        return strBuild.ToString();
    }
   
   public static void MakeResizable(this Panel pnl)
    {
        int dwCurStyle = Helper.GetWindowLong(pnl.Handle, GWL_STYLE);
        dwCurStyle = dwCurStyle | Helper.WS_RESIZABLE;
        Helper.SetWindowLong(pnl.Handle, GWL_STYLE, dwCurStyle);
    }
}

 protected override void OnLoad(EventArgs e)
    {
        imagePanel.MakeResizable();
        base.OnLoad(e);            
    }

其中 imgPanel 是 WinForm 應用程序中的一些面板