如何在 C# 中旋转标签？ [复制]

Question

我想显示一个旋转 90 度的标签（这样我就可以将它们放在表格顶部作为标题）。有没有简单的方法可以做到这一点？

Answer 1

您需要自己编写或使用自定义控件。

您可以从The Code Project 文章开始Customized Text - Orientated Controls in C# - Part I (Label Control)。这包含额外的功能，因此您应该可以根据需要对其进行修剪。

这里有一些有趣的代码：

/// <summary>
/// This is a lable, in which you can set the text in any direction/angle
/// </summary>

#region Orientation

//Orientation of the text

public enum Orientation
{
    Circle,
    Arc,
    Rotate
}

public enum Direction
{
    Clockwise,
    AntiClockwise
}

#endregion

public class OrientedTextLabel : System.Windows.Forms.Label
{
    #region Variables

    private double rotationAngle;
    private string text;
    private Orientation textOrientation;
    private Direction textDirection;

    #endregion

    #region Constructor

    public OrientedTextLabel()
    {
        //Setting the initial condition.
        rotationAngle = 0d;
        textOrientation = Orientation.Rotate;
        this.Size = new Size(105,12);
    }

    #endregion

    #region Properties

    [Description("Rotation Angle"),Category("Appearance")]
    public double RotationAngle
    {
        get
        {
            return rotationAngle;
        }
        set
        {
            rotationAngle = value;
            this.Invalidate();
        }
    }

    [Description("Kind of Text Orientation"),Category("Appearance")]
    public Orientation TextOrientation
    {
        get
        {
            return textOrientation;
        }
        set
        {
            textOrientation = value;
            this.Invalidate();
        }
    }

    [Description("Direction of the Text"),Category("Appearance")]
    public Direction TextDirection
    {
        get
        {
            return textDirection;
        }
        set
        {
            textDirection = value;
            this.Invalidate();
        }
    }

    [Description("Display Text"),Category("Appearance")]
    public override string Text
    {
        get
        {
            return text;
        }
        set
        {
            text = value;
            this.Invalidate();
        }
    }

    #endregion

    #region Method

    protected override void OnPaint(PaintEventArgs e)
    {
        Graphics graphics = e.Graphics;

        StringFormat stringFormat = new StringFormat();
        stringFormat.Alignment = StringAlignment.Center;
        stringFormat.Trimming = StringTrimming.None;

        Brush textBrush = new SolidBrush(this.ForeColor);

        //Getting the width and height of the text, which we are going to write
        float width = graphics.MeasureString(text,this.Font).Width;
        float height = graphics.MeasureString(text,this.Font).Height;

        //The radius is set to 0.9 of the width or height, b'cos not to
        //hide and part of the text at any stage
        float radius = 0f;
        if (ClientRectangle.Width<ClientRectangle.Height)
        {
            radius = ClientRectangle.Width *0.9f/2;
        }
        else
        {
            radius = ClientRectangle.Height *0.9f/2;
        }

        //Setting the text according to the selection
        switch (textOrientation)
        {
            case Orientation.Arc:
            {
                //Arc angle must be get from the length of the text.
                float arcAngle = (2*width/radius)/text.Length;
                if(textDirection == Direction.Clockwise)
                {
                    for (int i=0; i<text.Length; i++)
                    {
                        graphics.TranslateTransform(
                            (float)(radius*(1 - Math.Cos(arcAngle*i + rotationAngle/180 * Math.PI))),
                            (float)(radius*(1 - Math.Sin(arcAngle*i + rotationAngle/180*Math.PI))));
                        graphics.RotateTransform((-90 + (float)rotationAngle + 180*arcAngle*i/(float)Math.PI));
                        graphics.DrawString(text[i].ToString(), this.Font, textBrush, 0, 0);
                        graphics.ResetTransform();
                    }
                }
                else
                {
                    for (int i=0; i<text.Length; i++)
                    {
                        graphics.TranslateTransform(
                            (float)(radius*(1 - Math.Cos(arcAngle*i + rotationAngle/180*Math.PI))),
                            (float)(radius*(1 + Math.Sin(arcAngle*i + rotationAngle/180*Math.PI))));
                        graphics.RotateTransform((-90 - (float)rotationAngle - 180*arcAngle*i/(float)Math.PI));
                        graphics.DrawString(text[i].ToString(), this.Font, textBrush, 0, 0);
                        graphics.ResetTransform();
                    }
                }
                break;
            }
            case Orientation.Circle:
            {
                if (textDirection == Direction.Clockwise)
                {
                    for(int i=0;i<text.Length;i++)
                    {
                        graphics.TranslateTransform(
                            (float)(radius*(1 - Math.Cos((2*Math.PI/text.Length)*i + rotationAngle/180*Math.PI))),
                            (float)(radius*(1 - Math.Sin((2*Math.PI/text.Length)*i + rotationAngle/180*Math.PI))));
                        graphics.RotateTransform(-90 + (float)rotationAngle + (360/text.Length)*i);
                        graphics.DrawString(text[i].ToString(), this.Font, textBrush, 0, 0);
                        graphics.ResetTransform();
                    }
                }
                else
                {
                    for(int i=0;i<text.Length;i++)
                    {
                        graphics.TranslateTransform(
                            (float)(radius*(1 - Math.Cos((2*Math.PI/text.Length)*i + rotationAngle/180*Math.PI))),
                            (float)(radius*(1 + Math.Sin((2*Math.PI/text.Length)*i + rotationAngle/180*Math.PI))));
                        graphics.RotateTransform(-90 - (float)rotationAngle - (360/text.Length)*i);
                        graphics.DrawString(text[i].ToString(), this.Font, textBrush, 0, 0);
                        graphics.ResetTransform();
                    }

                }
                break;
            }

            case Orientation.Rotate:
            {
                //For rotation, who about rotation?
                double angle = (rotationAngle/180)*Math.PI;
                graphics.TranslateTransform(
                    (ClientRectangle.Width+(float)(height*Math.Sin(angle))-(float)(width*Math.Cos(angle)))/2,
                    (ClientRectangle.Height-(float)(height*Math.Cos(angle))-(float)(width*Math.Sin(angle)))/2);
                graphics.RotateTransform((float)rotationAngle);
                graphics.DrawString(text,this.Font,textBrush,0,0);
                graphics.ResetTransform();

                break;
            }
        }
    }
    #endregion
}

Answer 2

您还可以查看 Windows ToolStrip 控件。它有一个 TextDirection 选项，可以设置为 Vertical90 或 Vertical270，这会将您的标签文本旋转到适当的方向。

• 概述：ToolStrip Class (MSDN)

• Setting the property (docs.microsoft.com)

• Enumerated Values (docs.microsoft.com)