vb.net DataGridView使用循环把多个列标题文本HeaderText写入数组获取多列单元格的字符串的多种方法，每行后面注释

1. 使用循环遍历每个指定的列，逐一将列标题文本添加到数组中，再遍历每行获取多列单元格的字符串：

Dim columnHeaders As New List(Of String)
For Each col As DataGridViewColumn In DataGridView1.Columns
    If col.HeaderText = "Column1" OrElse col.HeaderText = "Column2" Then
        columnHeaders.Add(col.HeaderText)
    End If
Next
For Each row As DataGridViewRow In DataGridView1.Rows
    Dim cellValues As New List(Of String)
    For Each header In columnHeaders
        Dim cellValue As String = row.Cells(header).Value.ToString()
        cellValues.Add(cellValue)
    Next
    '处理多列单元格的字符串
Next

2. 使用 LINQ 查询语句获取指定列标题的数组，再使用 For Each 循环遍历每行获取多列单元格的字符串：

Dim columnHeaders = (From col As DataGridViewColumn In DataGridView1.Columns
                     Where col.HeaderText = "Column1" OrElse col.HeaderText = "Column2"
                     Select col.HeaderText).ToArray()
For Each row As DataGridViewRow In DataGridView1.Rows
    Dim cellValues As New List(Of String)
    For Each header In columnHeaders
        Dim cellValue As String = row.Cells(header).Value.ToString()
        cellValues.Add(cellValue)
    Next
    '处理多列单元格的字符串
Next

3. 使用 GetColumnCount 方法和 GetColumnHeaders 方法获取指定列标题的数组，再使用 GetCellValues 方法获取多列单元格的字符串：

Dim columnHeaders = DataGridView1.GetColumnHeaders().
                     Where(Function(h) h = "Column1" OrElse h = "Column2").ToArray()
Dim rowCount As Integer = DataGridView1.Rows.Count
Dim cellValues = DataGridView1.GetCellValues(0, 0, rowCount, columnHeaders.Length)
For Each rowValues In cellValues
    Dim cellValuesArray = rowValues.Cast(Of String).ToArray()
    '处理多列单元格的字符串
Next