1、怎样编写代码：如果textbox1和textbox2均不为空，则button1.enable=ture

2、怎样限制文本框内只能输入数字，而非其他。

注：最好代码举例，谢谢！！！

    Private Sub TextBox1_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TextBox1.TextChanged
        If (TextBox1.Text <> "" And TextBox2.Text <> "") Then
            Button1.Enabled = True
        Else
            Button1.Enabled = False
        End If
    End Sub

    Private Sub TextBox2_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TextBox2.TextChanged
        If (TextBox1.Text <> "" And TextBox2.Text <> "") Then
            Button1.Enabled = True
        Else
            Button1.Enabled = False
        End If
    End Sub

    Private Sub TextBox1_KeyPress(ByVal sender As System.Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextBox1.KeyPress
        '限制文本框只能输入数字
        If Not System.Text.RegularExpressions.Regex.IsMatch(e.KeyChar.ToString(), "[0-9]") Then
            e.Handled = True
        Else
            e.Handled = False
        End If
    End Sub

LS高人！

2楼的前两段代码可以合并，如下
    Private Sub TextBox1_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TextBox1.TextChanged,TextBox2.TextChanged
        If (TextBox1.Text <> "" And TextBox2.Text <> "") Then
            Button1.Enabled = True
        Else
            Button1.Enabled = False
        End If
    End Sub

多谢指教啊，呵呵！！！！

辽宁的大侠，精简，谢谢啊！！！

厉害嘛,我找好久了,多谢了!

二楼的数字限制如果包括小数点和负号就好了，以前没见过
System.Text.RegularExpressions.Regex.IsMatch(e.KeyChar.ToString(), "[0-9]")
的用法，可不可以解释一二？我是初学者，大家见笑了