vb.net DataGridView使用循环指定多个列标题文本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，逐一获取单元格的字符串：

For Each col As DataGridViewColumn In DataGridView1.Columns
    If col.HeaderText = "Column1" OrElse col.HeaderText = "Column2" Then
        For Each row As DataGridViewRow In DataGridView1.Rows
            Dim cellValue As String = row.Cells(col.Index).Value.ToString()
            '处理单元格的字符串
        Next
    End If
Next

2. 使用 LINQ 查询语句获取指定列的单元格字符串：

Dim result = From row As DataGridViewRow In DataGridView1.Rows.Cast(Of DataGridViewRow)()
             Select New With {
                 .Column1 = row.Cells("Column1").Value.ToString(),
                 .Column2 = row.Cells("Column2").Value.ToString()
             }
For Each item In result
    '处理每个单元格的字符串
Next

3. 使用 GetCellCount 方法和 GetCellValues 方法获取指定列的单元格字符串：

Dim col1Index As Integer = DataGridView1.Columns("Column1").Index
Dim col2Index As Integer = DataGridView1.Columns("Column2").Index
Dim rowCount As Integer = DataGridView1.Rows.Count
Dim cellValues = DataGridView1.GetCellValues(col1Index, 0, rowCount, col2Index + 1)
For Each rowValues In cellValues
    Dim col1Value As String = rowValues(col1Index).ToString()
    Dim col2Value As String = rowValues(col2Index).ToString()
    '处理每个单元格的字符串
Next