vb.net DataGridView循环列，获取是否包含有指定字符串的列内容的多种方法，代码后面带备注

以下是几种获取DataGridView指定字符串列内容的方法，注释在代码中：

方法一：使用for循环遍历列和行，判断单元格内容是否包含指定字符串

Dim targetString As String = "指定字符串"
Dim targetColumns As List(Of Integer) = New List(Of Integer)()
For columnIndex As Integer = 0 To dataGridView1.Columns.Count - 1
    For rowIndex As Integer = 0 To dataGridView1.Rows.Count - 1
        If dataGridView1.Rows(rowIndex).Cells(columnIndex).Value.ToString().Contains(targetString) Then
            ' 如果包含指定字符串，将列索引加入List
            targetColumns.Add(columnIndex)
            Exit For ' 如果该列有单元格包含指定字符串，跳出该列的循环
        End If
    Next
Next
' targetColumns 中存储的是包含指定字符串的列的索引

方法二：使用LINQ查询，获取包含指定字符串的列

Dim targetString As String = "指定字符串"
Dim targetColumns As List(Of Integer) = (
    From column As DataGridViewColumn In dataGridView1.Columns
    Where (
        From row As DataGridViewRow In dataGridView1.Rows
        Where Convert.ToString(row.Cells(column.Index).Value).Contains(targetString)
        Select row
    ).Any()
    Select column.Index
).ToList()
' targetColumns 中存储的是包含指定字符串的列的索引

方法三：使用DataGridView控件的CellFormatting事件，获取包含指定字符串的列

Dim targetString As String = "指定字符串"
Dim targetColumns As List(Of Integer) = New List(Of Integer)()
Private Sub dataGridView1_CellFormatting(sender As Object, e As DataGridViewCellFormattingEventArgs) Handles dataGridView1.CellFormatting
    If e.RowIndex = 0 Then ' 只在第一行格式化时判断列内容
        If e.Value IsNot Nothing AndAlso e.Value.ToString().Contains(targetString) Then
            targetColumns.Add(e.ColumnIndex)
        End If
    End If
End Sub
' targetColumns 中存储的是包含指定字符串的列的索引