c# - 当我显示它时，我的自定义 progressBar 表单挂起

Question

我制作了一个表单，它起到了进度条的作用，这是我制作的代码

  public partial class PXProgressBar : Form
    {
        public delegate bool CancelEvent();
        public event CancelEvent cancel_e;

        public Boolean ProcessCancelled
        {
            get;
            set;
        }
        public PXProgressBar(bool EnableCancel) 
        {
            InitializeComponent();
            ProcessCancelled = false;
            progressBar1.Minimum = 0;
            if (!EnableCancel)
                Cancelbtn.Visible = false;

        }
        public  void increament(int step)
        {
            if (progressBar1.Value < progressBar1.Maximum-1)
            {
                progressBar1.Value++;
                progressBar1.Caption = progressBar1.Value.ToString() + " of " + progressBar1.Maximum;
                progressBar1.Refresh();

            }

            else
            {
                progressBar1.Value++;
                progressBar1.Caption = progressBar1.Value.ToString() + " of " + progressBar1.Maximum;
                if (this.TopMost)
                    this.TopMost = false;
                this.Update();
                this.Hide();
                this.WindowState = FormWindowState.Minimized;
               // this.Dispose();
            }

        }
        public void SetMaximum(int MaximumValue)
        {
            if (MaximumValue <= 0)
            {
                progressBar1.Maximum = 0;
                return;
            }
            if (progressBar1.Minimum != 0 && MaximumValue < progressBar1.Minimum)
            {
                progressBar1.Maximum = progressBar1.Minimum;
                return;
            }
            progressBar1.Maximum = MaximumValue;


        }
        public void SetMinimum(int MinimumValue)
        {
            progressBar1.Value = 0;
            if (MinimumValue <= 0)
            {

                progressBar1.Minimum = 0;
                return;
            }
            if (progressBar1.Maximum != 100 && MinimumValue > progressBar1.Maximum)
            {
                progressBar1.Minimum = progressBar1.Maximum;
                return;
            }
            progressBar1.Minimum= MinimumValue;
        }
        public void SetTitle(string ProcessTitle)
        {
            this.ProgressTitlelb.Text =ProcessTitle;// ProcessTitle;
            //this.ProgressTitlelb.Left = (this.panel1.Width - this.ProgressTitlelb.Width) / 2;
            //this.ProgressTitlelb.Top = (this.panel1.Height - this.ProgressTitlelb.Height) / 2;
            this.Update();
        }

        private void Cancelbtn_Click(object sender, EventArgs e)
        {

            ProcessCancelled = true;
            bool disposeRequired =cancel_e();
            if(disposeRequired)
             this.Dispose();
        }

        private void PXProgressBar_Shown(object sender, EventArgs e)
        {
            this.Update();
        }

    }

我通过这段代码调用表单

  if (ProgressBar == null)
   ProgressBar = new PXProgressBar(true);
   ProgressBar.SetTitle("Saving ...");
   ProgressBar.SetMinimum(0);
   ProgressBar.SetMaximum(100);
   ProgressBar.TopMost = true;
   ProgressBar.Show();
   Application.DoEvents();

关于过去几行是在一个通过线程调用的函数中 但是当我运行它时表单挂起所以我不能在表单中设置一个取消按钮让用户取消操作

Answer 1

您的代码看起来应该没问题，所以我只能假设您在 UI 线程上执行长时间运行的操作，这会导致 UI 看起来像挂起。您需要在后台线程上执行长时间运行的操作，以便 UI 线程保持足够的响应能力以响应按钮点击等。如果您咨询您的 friend Google，有很多关于此的文章。

更多信息请点击此处 http://www.idevforfun.com/index.php/2010/01/10/windows-ui-threading/

我同意 Skizz 对 DoEvents 调用的看法……只有极少数情况下才需要该调用，而且大多数情况下它是在框架本身中使用的。