切换参数中的表达式术语"大小写"无效

我得到一个"错误1当前上下文中不存在名称'Switch'"和我的交换机语句中的"无效表达式术语'case'"错误.我的问题是这些错误意味着什么？这是开关

private void buttonRead_Click(object sender, EventArgs e)
        {
            int Selected = listColours.SelectedIndex;
            Colours newColour;

            Switch(Selected)
            {
                case 0:
                newColour = Colours.red;
                MessageBox.Show(newColour.ToString(), "Output", MessageBoxButtons.OK, MessageBoxIcon.Information);
                break;

                case 1:
                newColour = Colours.orange;
                MessageBox.Show(newColour.ToString(), "Output", MessageBoxButtons.OK, MessageBoxIcon.Information);
                break;

                case 2:
                newColour = Colours.yellow;
                MessageBox.Show(newColour.ToString(), "Output", MessageBoxButtons.OK, MessageBoxIcon.Information);
                break;

                case 3:
                newColour = Colours.green;
                MessageBox.Show(newColour.ToString(), "Output", MessageBoxButtons.OK, MessageBoxIcon.Information);
                break;

                case 4:
                newColour = Colours.blue;
                MessageBox.Show(newColour.ToString(), "Output", MessageBoxButtons.OK, MessageBoxIcon.Information);
                break;

                case 5:
                newColour = Colours.purple;
                MessageBox.Show(newColour.ToString(), "Output", MessageBoxButtons.OK, MessageBoxIcon.Information);
                break;
            }

King King.. 8

C#区分大小写,因此您必须准确地键入关键字,更改Switch为switch它应该有效.