DataGridView最右边的列用户增加大小无法正常工作 [英] DataGridView rightmost column user increase size not working

问题描述

我在WinForm上的DataGridView有一个奇怪的问题。我可以通过鼠标调整所有列的大小，但最右边的内容只能缩小，而不能增加大小。

I have a strange issue with a DataGridView on a WinForm. I can resize all columns via mouse, but for the rightmost I can only shrink and not increase the size.

有人知道如何解决这个问题？

Does anyone know how to solve this?

推荐答案

这是设计使然。单击/按住鼠标按钮时，鼠标会被捕获并且无法离开客户区，从而阻止了调整大小。

This is by design. When you Click/Hold your mouse button, the mouse is captured and cannot leave the client area, with the effect of blocking the resize. You have to give it a push.

我尝试不进行P / Invoke释放捕获。

看看是否适用

I tried not to P/Invoke to release the capture.
See if this works for you (of course if any AutoSize mode is set, nothing will happen).

private bool IsLastColumn = false;
private bool IsMouseDown = false;
private int MouseLocationX = 0;

private void dataGridView1_MouseDown(object sender, MouseEventArgs e)
{
   int _LastColumnIndex = dataGridView1.Columns.Count - 1;
   //Check if the mousedown is contained in last column boundaries
   //In the middle of it because clicking the divider of the row before
   //the last may be seen as inside the last too.
   Point _Location = new Point(e.X - (dataGridView1.Columns[_LastColumnIndex].Width / 2), e.Y);
   if (dataGridView1.GetColumnDisplayRectangle(_LastColumnIndex, true).Contains(_Location))
   {
      //Store a positive checks and the current mouse position
      this.IsLastColumn = true;
      this.IsMouseDown = true;
      this.MouseLocationX = e.Location.X;
   }
}

private void dataGridView1_MouseMove(object sender, MouseEventArgs e)
{
   //If it's the last column and the left mouse button is pressed...
   if ((this.IsLastColumn == true) && (this.IsMouseDown == true) && (e.Button == System.Windows.Forms.MouseButtons.Left))
   {
      // Adding the width of the vertical scrollbar, if any.
      int cursorXPosition = e.X;
      if (dataGridView1.Controls.OfType<VScrollBar>().Where(s => s.Visible).Count() > 0)
      {
          cursorXPosition += SystemInformation.VerticalScrollBarWidth;
      }

      //... calculate the offset of the movement.
      //You'll have to play with it a bit, though
      int _ColumnWidth = dataGridView1.Columns[dataGridView1.Columns.Count - 1].Width;
      int _ColumnWidthOffset = _ColumnWidth + (e.X - this.MouseLocationX) > 0 ? (e.X - this.MouseLocationX) : 1;
      //If mouse pointer reaches the limit of the clientarea...
      if ((_ColumnWidthOffset > -1) && (cursorXPosition >= dataGridView1.ClientSize.Width - 1))
      {
         //...resize the column and move the scrollbar offset
         dataGridView1.HorizontalScrollingOffset = dataGridView1.ClientSize.Width + _ColumnWidth + _ColumnWidthOffset;
         dataGridView1.Columns[dataGridView1.Columns.Count - 1].Width = _ColumnWidth + _ColumnWidthOffset;
      }
   }
}

private void dataGridView1_MouseUp(object sender, MouseEventArgs e)
{
      this.IsMouseDown = false;
      this.IsLastColumn = false;
}

这篇关于DataGridView最右边的列用户增加大小无法正常工作的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！