Winform应用程序实现通用遮罩层二

之前先后发表过：《Winform应用程序实现通用遮罩层》、《Winform应用程序实现通用消息窗口》，这两款遮罩层其实都是基于弹出窗口的，今天为大家分享一个比较简单但界面相对友好的另一种实现方案，废话不多说，直接进入主题。

一、实现思路（解决问题顺序）：

透明遮罩：

1.实现可设置透明的Panel控件（MaskPanel）；

2.Panel控件（MaskPanel）能够覆盖父容器（一般是当前窗体form对象）客户区区域（即：与父容器客户区区域大小相同），并处于最上层，保证父容器上的任何控件都被盖住并保证不可用；

3.Panel控件（MaskPanel）必需实现随着父容器大小的改变而改变；

4.Panel控件（MaskPanel）上可呈现以表示正在加载的动图或者文字，并且居中；

异步：

实现的方法有很多，比如异步委托、Task等，而这是在winform项目中，此次就直接使用BackgroundWorker

二、关键解决方案：

1.可设置透明控件：通过自定义控件，并重写CreateParams（其中： cp.ExStyle |= 0x00000020;）、OnPaint（其中：labelBorderPen、labelBackColorBrush的Color=Color.FromArgb(_alpha, this.BackColor)）两个方法即可；

2.能够覆盖父容器客户区区域：this.Size = this.Parent.ClientSize;this.Left = 0;this.Top = 0;

3.随着父容器大小的改变而改变：this.Anchor = AnchorStyles.Left | AnchorStyles.Top | AnchorStyles.Right | AnchorStyles.Bottom;

4.呈现以表示正在加载的动图或者文字，并且居中：

添加PictureBox，设置Image为loading.gif动图，SizeMode = System.Windows.Forms.PictureBoxSizeMode.AutoSize; Point Location = new Point(this.Location.X + (this.Width - pictureBox_Loading.Width) / 2, this.Location.Y + (this.Height - pictureBox_Loading.Height) / 2);//居中

好了，最后贴出实现的源代码：

MaskPanel：

100

101

public partial class MaskPanel : Control
{
    private System.ComponentModel.Container components = new System.ComponentModel.Container();
 
    private bool _isTransparent = true;//是否透明
    [Category("透明"), Description("是否使用透明,默认为True")]
    public bool IsTransparent
    {
        get { return _isTransparent; }
        set { _isTransparent = value; }
    }
 
    private int _alpha = 125;//设置透明度
    [Category("透明"), Description("设置透明度")]
    public int Alpha
    {
        get { return _alpha; }
        set { _alpha = value; }
    }
 
 
    public MaskPanel(Control parent)
        : this(parent, 125)
    {
 
    }
 
    /// <summary>
    /// 初始化加载控件
    /// </summary>
    /// <param name="Alpha"透明度</param>
    public MaskPanel(Control parent, int alpha)
    {
        SetStyle(ControlStyles.Opaque, true);//设置背景透明
        base.CreateControl();
        _alpha = alpha;
        parent.Controls.Add(this);
        this.Parent = parent;
        this.Size = this.Parent.ClientSize;
        this.Left = 0;
        this.Top = 0;
        this.Anchor = AnchorStyles.Left | AnchorStyles.Top | AnchorStyles.Right | AnchorStyles.Bottom;
        this.BringToFront();
 
        PictureBox pictureBox_Loading = new PictureBox();
        pictureBox_Loading.BackColor = System.Drawing.Color.Transparent;
        pictureBox_Loading.Image = Properties.Resources.loading;
        pictureBox_Loading.Name = "pictureBox_Loading";
        pictureBox_Loading.SizeMode = System.Windows.Forms.PictureBoxSizeMode.AutoSize;
        Point Location = new Point(this.Location.X + (this.Width - pictureBox_Loading.Width) / 2, this.Location.Y + (this.Height - pictureBox_Loading.Height) / 2);//居中
        pictureBox_Loading.Location = Location;
        pictureBox_Loading.Anchor = AnchorStyles.None;
        this.Controls.Add(pictureBox_Loading);
 
 
        this.Visible = false;
    }
 
    protected override CreateParams CreateParams
    {
        get
        {
            CreateParams cp = base.CreateParams;
            cp.ExStyle |= 0x00000020; // 开启 WS_EX_TRANSPARENT,使控件支持透明
            return cp;
        }
    }
 
    protected override void OnPaint(PaintEventArgs pe)
    {
        Pen labelBorderPen;
        SolidBrush labelBackColorBrush;
        if (_isTransparent)
        {
            Color cl = Color.FromArgb(_alpha, this.BackColor);
            labelBorderPen = new Pen(cl, 0);
            labelBackColorBrush = new SolidBrush(cl);
        }
        else
        {
            labelBorderPen = new Pen(this.BackColor, 0);
            labelBackColorBrush = new SolidBrush(this.BackColor);
        }
        base.OnPaint(pe);
        pe.Graphics.DrawRectangle(labelBorderPen, 0, 0, this.Width, this.Height);
        pe.Graphics.FillRectangle(labelBackColorBrush, 0, 0, this.Width, this.Height);
    }
 
    protected override void Dispose(bool disposing)
    {
        if (disposing)
        {
            if (!((components == null)))
            {
                components.Dispose();
            }
        }
        base.Dispose(disposing);
    }
 
}

为了实现通用，同时保证所有的窗体都有异步执行并显示遮罩效果，故此处采用定义一个窗体基类：FormBase，里面定义一个受保护的DoWorkAsync方法，代码如下：

public partial class FormBase : Form
{
    public FormBase()
    {
        InitializeComponent();
        this.StartPosition = FormStartPosition.CenterParent;
    }
 
 
 
    /// <summary>
    /// 多线程异步后台处理某些耗时的数据，不会卡死界面
    /// </summary>
    /// <param name="workFunc">Func委托，包装耗时处理（不含UI界面处理），示例：(o)=>{ 具体耗时逻辑; return 处理的结果数据 }</param>
    /// <param name="funcArg">Func委托参数，用于跨线程传递给耗时处理逻辑所需要的对象，示例：String对象、JObject对象或DataTable等任何一个值</param>
    /// <param name="workCompleted">Action委托，包装耗时处理完成后，下步操作（一般是更新界面的数据或UI控件），示列：(r)=>{ datagirdview1.DataSource=r; }</param>
    protected void DoWorkAsync(Func<object, object> workFunc, object funcArg = null, Action<object> workCompleted = null)
    {
        var bgWorkder = new BackgroundWorker();
 
 
        //Form loadingForm = null;
        Control loadingPan = null;
        bgWorkder.WorkerReportsProgress = true;
        bgWorkder.ProgressChanged += (s, arg) =>
        {
            if (arg.ProgressPercentage > 1) return;
 
            #region Panel模式
 
            var result = this.Controls.Find("loadingPan", true);
            if (result == null || result.Length <= 0)
            {
                loadingPan = new MaskPanel(this)
                {
                    Name = "loadingPan"
                };
            }
            else
            {
                loadingPan = result[0];
            }
 
            loadingPan.BringToFront();
            loadingPan.Visible = true;
 
            #endregion
        };
 
        bgWorkder.RunWorkerCompleted += (s, arg) =>
        {
 
            #region Panel模式
 
            if (loadingPan != null)
            {
                loadingPan.Visible = false;
            }
 
            #endregion
 
            bgWorkder.Dispose();
 
            if (workCompleted != null)
            {
                workCompleted(arg.Result);
            }
        };
 
        bgWorkder.DoWork += (s, arg) =>
        {
            bgWorkder.ReportProgress(1);
            var result = workFunc(arg.Argument);
            arg.Result = result;
            bgWorkder.ReportProgress(100);
        };
 
        bgWorkder.RunWorkerAsync(funcArg);
    }
 
 
}

使用示例如下：

private void button1_Click(object sender, EventArgs e)
{
    int startNo = 20;
    button1.Enabled = false;
    this.DoWorkAsync((o) => //耗时逻辑处理(此处不能操作UI控件，因为是在异步中)
    {
        int result = 0;
        for (int i = 1; i <= Convert.ToInt32(o); i++)
        {
            result += i;
            Thread.Sleep(500);
        }
        return result;
 
    }, startNo, (r) => //显示结果（此处用于对上面结果的处理，比如显示到界面上）
    {
        label1.Text = r.ToString();
        button1.Enabled = true;
    });
 
 
 
}

效果图就不贴出来了，大家可以COPY上面的所有代码，即可测试出效果。

2017年3月15日优化补充：

为了提高异步加载编码的方便，特优化了DoWorkAsync方法，将返回值由object改为dynamic，这样就比较方便，直接返回，直接使用

方法签名如下：

protected void DoWorkAsync(Func<object, dynamic> workFunc, object funcArg = null, Action<dynamic> workCompleted = null)

其余逻辑实现保持不变。

使用更简单，如下图示：

出处：https://www.cnblogs.com/zuowj/p/6497142.html

posted on 2022-09-20 11:00 jack_Meng 阅读(432) 评论(0) 编辑收藏举报

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Winform应用程序实现通用遮罩层二

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