通过 DataGridView 数据填充 TextBox

Question

DataGridView1 将填充 1 行或 2 行或 3 行 .. 最多 5 行 .. 我有 4 列 我希望当我单击 Button1 时，从 1 到 20 的 TextBox 将被 DataGridView1 上显示的数据填充 从 1 到 4 的 TextBox 将被第一行填充 从 5 到 8 的文本框将由第二行填充 9到12的TextBox将被第三行填充 13到16的TextBox将被第四行填充 17到20的TextBox将被第五行填充 例如..如果我在 DataGridView1 上只有 3 行，那么在这种情况下，从 13 到 20 的 TextBox 将为空。 当 DataGridView1 的 5 行被填满时，我不会有任何问题，但是当我在 DataGridView1 上只有 4 或 3 或 2 或 1 行时，我会遇到问题并且它不起作用。

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles       Button1.Click
If DataGridView1.Rows.Count = 0 Then
TextBox1.Text = DataGridView1.Rows.Item(0).Cells(0).Value.ToString()
TextBox2.Text = DataGridView1.Rows.Item(0).Cells(1).Value.ToString()
TextBox3.Text = DataGridView1.Rows.Item(0).Cells(2).Value.ToString()
        TextBox4.Text = DataGridView1.Rows.Item(0).Cells(3).Value.ToString()
    ElseIf DataGridView1.Rows.Count = 1 Then
        TextBox5.Text = DataGridView1.Rows.Item(1).Cells(0).Value.ToString()
        TextBox6.Text = DataGridView1.Rows.Item(1).Cells(1).Value.ToString()
        TextBox7.Text = DataGridView1.Rows.Item(1).Cells(2).Value.ToString()
        TextBox8.Text = DataGridView1.Rows.Item(1).Cells(3).Value.ToString()
    ElseIf DataGridView1.Rows.Count = 2 Then
        TextBox9.Text = DataGridView1.Rows.Item(2).Cells(0).Value.ToString()
        TextBox10.Text = DataGridView1.Rows.Item(2).Cells(1).Value.ToString()
        TextBox11.Text = DataGridView1.Rows.Item(2).Cells(2).Value.ToString()
        TextBox12.Text = DataGridView1.Rows.Item(2).Cells(3).Value.ToString()
    ElseIf DataGridView1.Rows.Count = 3 Then
        TextBox13.Text = DataGridView1.Rows.Item(3).Cells(0).Value.ToString()
        TextBox14.Text = DataGridView1.Rows.Item(3).Cells(1).Value.ToString()
        TextBox15.Text = DataGridView1.Rows.Item(3).Cells(2).Value.ToString()
        TextBox16.Text = DataGridView1.Rows.Item(3).Cells(3).Value.ToString()
    ElseIf DataGridView1.Rows.Count = 4 Then
        TextBox17.Text = DataGridView1.Rows.Item(4).Cells(0).Value.ToString()
        TextBox18.Text = DataGridView1.Rows.Item(4).Cells(1).Value.ToString()
        TextBox19.Text = DataGridView1.Rows.Item(4).Cells(2).Value.ToString()
 TextBox20.Text =DataGridView1.Rows.Item(4).Cells(3).Value.ToString()
End If
End Sub

Answer 1

我会这样写代码：

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
    If DataGridView1.Rows.Count > 4 Then
        TextBox17.Text = DataGridView1.Rows.Item(4).Cells(0).Value.ToString()
        TextBox18.Text = DataGridView1.Rows.Item(4).Cells(1).Value.ToString()
        TextBox19.Text = DataGridView1.Rows.Item(4).Cells(2).Value.ToString()
        TextBox20.Text = DataGridView1.Rows.Item(4).Cells(3).Value.ToString()
    End If
    If DataGridView1.Rows.Count > 3 Then
        TextBox13.Text = DataGridView1.Rows.Item(3).Cells(0).Value.ToString()
        TextBox14.Text = DataGridView1.Rows.Item(3).Cells(1).Value.ToString()
        TextBox15.Text = DataGridView1.Rows.Item(3).Cells(2).Value.ToString()
        TextBox16.Text = DataGridView1.Rows.Item(3).Cells(3).Value.ToString()
    End If
    If DataGridView1.Rows.Count > 2 Then
        TextBox9.Text = DataGridView1.Rows.Item(2).Cells(0).Value.ToString()
        TextBox10.Text = DataGridView1.Rows.Item(2).Cells(1).Value.ToString()
        TextBox11.Text = DataGridView1.Rows.Item(2).Cells(2).Value.ToString()
        TextBox12.Text = DataGridView1.Rows.Item(2).Cells(3).Value.ToString()
    End If
    If DataGridView1.Rows.Count > 1 Then
        TextBox5.Text = DataGridView1.Rows.Item(1).Cells(0).Value.ToString()
        TextBox6.Text = DataGridView1.Rows.Item(1).Cells(1).Value.ToString()
        TextBox7.Text = DataGridView1.Rows.Item(1).Cells(2).Value.ToString()
        TextBox8.Text = DataGridView1.Rows.Item(1).Cells(3).Value.ToString()
    End If
    If DataGridView1.Rows.Count > 0 Then
        TextBox1.Text = DataGridView1.Rows.Item(0).Cells(0).Value.ToString()
        TextBox2.Text = DataGridView1.Rows.Item(0).Cells(1).Value.ToString()
        TextBox3.Text = DataGridView1.Rows.Item(0).Cells(2).Value.ToString()
        TextBox4.Text = DataGridView1.Rows.Item(0).Cells(3).Value.ToString()
    End If
End Sub


Public Class TestItem
    Public Property Prop1 As String
    Public Property Prop2 As String
    Public Property Prop3 As String
    Public Property Prop4 As String

    Public Sub New(P1 As String, P2 As String, P3 As String, P4 As String)
        Prop1 = P1
        Prop2 = P2
        Prop3 = P3
        Prop4 = P4
    End Sub
End Class

Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
    Dim source As New List(Of TestItem)
    source.Add(New TestItem("a", "b", "c", "d"))
    source.Add(New TestItem("e", "f", "g", "h"))
    source.Add(New TestItem("i", "j", "k", "l"))
    source.Add(New TestItem("m", "n", "o", "p"))
    'source.Add(New TestItem("q", "r", "s", "t"))

    DataGridView1.DataSource = source
End Sub

不要将Count 属性与Rows' 集合Index 混淆，它是从0 开始的。在您的代码中，您正在检查DataGridView1.Rows.Count = 0，然后访问DataGridView1.Rows.Item(0)。如果 Rows.Count 为 0，则 Rows.Items(0) 不存在，因为它将是第一行，但由于行数为 0，因此网格中没有行。