获取实际列宽

Question

我正在以编程方式构建一个 DataGridView 表并将其放置在表单上的 GroupBox 中。

我插入数据，然后自动调整列大小以适应数据。然后我想将 groupbox 的大小调整为 DataGridView 的大小。对于每一列和每一行，我得到它们各自的宽度和高度，这在技术上应该是准确的，并更新面板和整体 DataGridView 大小。

问题是 Column.Width 总是返回 100 像素，无论其实际大小如何（见截图：实际列宽约为 30 像素，而不是 100）。如果我手动输入宽度 = 90 像素，则调整大小非常准确！

matrix = new DataGridView();
//modify behaviour
matrix.ColumnHeadersVisible = false;
matrix.AllowUserToResizeColumns = false;
matrix.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.AllCells;
matrix.RowHeadersVisible = false;
matrix.AllowUserToResizeRows = false;
//modify positioning
matrix.Location = new Point(10, 20);
//matrix.Anchor = (AnchorStyles)(AnchorStyles.Left | AnchorStyles.Top | AnchorStyles.Bottom | AnchorStyles.Right);
matrix.Dock = DockStyle.Fill;
//set the size of the matrix
matrix.ColumnCount = col;
matrix.RowCount = row;


//Data now inserted...
matrix.AutoResizeColumns(); //correctly resizes the columns

int height = 0;
foreach (DataGridViewRow row in matrix.Rows)
{
    height += row.Height;
}
height += matrix.ColumnHeadersHeight;

int width = 0;
foreach (DataGridViewColumn col in matrix.Columns)
{
    width += col.Width;
    //PROBLEM: Width always  = 100 pixels.
}
width += matrix.RowHeadersWidth;
//width = 90; //override width manually
matrix.Size = new Size(width + 2, height + 2);
panel.Size = new Size(matrix.Width, matrix.Height);

面板这么大是因为宽度不是 90px 而是大约 357，这是错误的！

编辑：部分修复 我找到了一种方法来获得正确的单元格宽度：

DataGridView.Rows[0].Cells[0].ContentBounds.Width
//ContentBounds = a rectangle with the exact dimensions of that cell

我现在可以将 DataGridView 设置为正确的大小，但前提是它没有停靠到填充。设置 matrix.Dock = DockStyle.Fill 会阻止正确调整大小。

Answer 1

我猜那是因为您正在自动调整行中的列大小：

matrix.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.AllCells;

尝试将其更改为：

matrix.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.None;

Answer 2

我已经弄清楚问题所在了：

1. DataGridView.Dock = DockStyle.Fill 阻止 DataGridView.AutoResizeColumns() 方法执行任何操作。

2. Rectangle rect = matrix.Rows[0].Cells[0].ContentBounds 获取包含单元格值的矩形的尺寸在 AutoResizeColumns() 之后没有更新

3. 我尝试手动设置列，但按照 heq 的建议，AutoSizeColumnsMode 必须设置为 None 才能修改宽度。

4. 我手动调整了每列的宽度，单元格内每个字符为10px

最终解决方案

/* Create the DataGridView */
matrix = new DataGridView();
//modify behaviour
matrix.ColumnHeadersVisible = false;
// matrix.columnhea
matrix.AllowUserToResizeColumns = false;
matrix.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.None;
matrix.RowHeadersVisible = false;
matrix.AllowUserToResizeRows = false;
matrix.ReadOnly = true;
//modify positioning
matrix.Location = new Point(10, 20);
//matrix.Dock = DockStyle.Fill;
matrix.Anchor = (AnchorStyles)(AnchorStyles.Left | AnchorStyles.Top | AnchorStyles.Bottom | AnchorStyles.Right);
//set the size of the matrix
matrix.ColumnCount = cols;
matrix.RowCount = rows;

panel.Controls.Add(matrix);

/* Set the data contents (not shown) */
...

/* Adjust the width of columns */
int width = 0;
int height = 0;

for(int c = 0; c < cols; c++) 
{
  int largest = 0; //largest number of characters in cell
  for(int r = 0; r < rows; r++) 
  {
      int len = matrix.Rows[r].Cells[c].Value.ToString().Length;
      if (len > largest)
      {
          largest = len;
      }
  }
  matrix.Columns[c].Width = largest * 10;
  width += largest * 10;
}

/* Get height of table */
foreach (DataGridViewRow row in matrix.Rows)
{
    height += row.Height;
}

/* Set the DataGridView Size and Parent Panel size */
//Note: first set the parent panel width, the table is anchored to all of its edges
// as such table wont resize correctly if the panel isn't up to size first
panel.Size = new Size(width + 20, height + 30);
matrix.Size = new Size(width + 3, height + 3); //is it 1px per row and col?

/* Parent Panel settings kept to default, no modifications */