为什么Cast(CType/DirectCast)控件与隐式转换

假设我在webforms GridViewRow中有一个控件...

在RowDataBound事件中,我可以使用以下任何方法访问控件.我一直以来一直使用DirectCast:

Protected Sub gv_RowDataBound(sender As Object, e As GridViewRowEventArgs) Handles gv.RowDataBound
    Select Case e.Row.RowType
        Case DataControlRowType.DataRow
            ' 1) Dim ltl_abc As Literal = DirectCast(e.Row.FindControl("ltl_abc"), Literal)
            ' 2) Dim ltl_abc As Literal = CType(e.Row.FindControl("ltl_abc"), Literal)
            ' 3) Dim ltl_abc As Literal = e.Row.FindControl("ltl_abc")

使用任何特定方法有什么好处吗？我猜DirectCast稍微有点效率,但可能容易出错,但隐式转换是否有任何危险(选项3)？

从历史上看,在我尝试为控件的属性实际赋值之前,我从未见过任何错误,这让我觉得这第一步不是那么重要吗？

请注意,这不是DirectCast与CType的讨论,更多的是关于在这里是否需要施法？

更新清晰

Protected Sub gv_RowDataBound(sender As Object, e As GridViewRowEventArgs) Handles gv.RowDataBound
    Select Case e.Row.RowType
        Case DataControlRowType.DataRow

            ' This works fine, but no explicit casting is done:
            Dim ltl_abc As Literal = e.Row.FindControl("ltl_abc") ' no (explicit) cast
            ltl_abc.Text = "Hello World"

            ' This also works until I try to access the object's properties
            Dim ltl_abc As Literal = DirectCast(e.Row.FindControl("NonExistentId"), Literal)

那么为什么开发人员应该投射(在这个例子中),或者这个例子过于简单？