MeasureCharacterRanges甚至不准确吗？

Question

当然，众所周知，Graphics.MeasureString方法存在填充问题，因此您使用Graphics.MeasureCharacterRanges，但正如您在此处所见：

测量不正确。这是MeasureCharacterRanges的问题还是我的代码？我该如何解决？

这是我的代码：

    'Draw the selection cursor
    If Me.Focused Then
        Dim cX As Integer = 1, cY As Integer = 5, c As Char
        For i As Integer = 0 To Me.SelectionStart - 1
            c = Me.Text(i)

            If c = ControlChars.CrLf Then
                cY += Me.Font.Height
            Else
                Dim w As Integer = MeasureCharacter(g, c, Me.Font).Width
                g.DrawRectangle(Pens.Black, cX, cY, w, Me.Font.Height) 'Draw a rectangle for debugging
                cX += w
            End If
        Next

        g.DrawLine(Pens.Black, cX, cY, cX, cY + Me.Font.Height)
    End If
End Sub

Protected Function MeasureCharacter(ByVal g As Graphics, ByVal c As Char, ByVal f As Font) As Size
    Dim cr() As CharacterRange = {New CharacterRange(0, 1)}
    Dim sfmt As New StringFormat()
    sfmt.FormatFlags = StringFormatFlags.MeasureTrailingSpaces
    sfmt.SetMeasurableCharacterRanges(cr)
    Return g.MeasureCharacterRanges(c.ToString(), f, Me.ClientRectangle, sfmt)(0).GetBounds(g).Size.ToSize()
End Function

Answer 1

测量单个字符的长度不考虑字符组之间出现的字距，因此字符长度的总和不等于字符串的长度。

如果你查看你的示例文本，你可以看到“Sprint”结尾处的“t”和“Textbox”开头的“T”之间的字距，字符比你想要的更接近。期待各自的长度。