问题描述

我需要能够旋转标签中的文本并将其左对齐、右对齐或居中对齐.到目前为止，我可以在派生标签的 onPaint 方法中使用此代码进行旋转:

I need to be able to rotate text in a label and align it to the left, right or center. So far I am able to do rotation with this code in the derived label's onPaint method:

 float width = graphics.MeasureString(Text, this.Font).Width;
 float height = graphics.MeasureString(Text, this.Font).Height;

 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(270f);
 graphics.DrawString(Text, this.Font, textBrush, new PointF(0,0), stringFormat);
 graphics.ResetTransform();

而且效果很好.我可以看到文字旋转了 270 度.

And it works fine. I can see text rotated 270 degrees.

但是当我尝试在 stringFormat 中设置对齐时，它变得疯狂，我无法弄清楚发生了什么.

But when I try to set alignment in stringFormat it goes crazy, and I can't figure out what's going on.

如何让文本旋转 270 度并向上对齐?

How can I have text rotated by 270 degrees and align it to up?

推荐答案

如果有人在寻找提示，这里是 0、90、180、270 和 360 度旋转的解决方案，其中 StringAligment 可以工作.

In case somebody was looking for tips, here is the solution for 0, 90, 180, 270, and 360 degrees rotation, where StringAligment works.

一件事是选择正确的点将原点移动到，第二件事是根据旋转修改显示矩形.

One thing was choosing the right point for moving the origin to, and the second one was to modify the display rectangle according to rotation.

StringFormat format = new StringFormat();
format.Alignment = StringAlignment.Center;

SizeF txt = e.Graphics.MeasureString(Text, this.Font);
SizeF sz = e.Graphics.VisibleClipBounds.Size;

//90 degrees
e.Graphics.TranslateTransform(sz.Width, 0);
e.Graphics.RotateTransform(90);
e.Graphics.DrawString(Text, this.Font, Brushes.Black, new RectangleF(0, 0, sz.Height, sz.Width), format);
e.Graphics.ResetTransform();

//180 degrees
e.Graphics.TranslateTransform(sz.Width, sz.Height);
e.Graphics.RotateTransform(180);
e.Graphics.DrawString(Text, this.Font, Brushes.Black, new RectangleF(0, 0, sz.Width, sz.Height), format);
e.Graphics.ResetTransform();

//270 degrees
e.Graphics.TranslateTransform(0, sz.Height);
e.Graphics.RotateTransform(270);
e.Graphics.DrawString(Text, this.Font, Brushes.Black, new RectangleF(0, 0, sz.Height, sz.Width), format);
e.Graphics.ResetTransform();

//0 = 360 degrees
e.Graphics.TranslateTransform(0, 0);
e.Graphics.RotateTransform(0);
e.Graphics.DrawString(Text, this.Font, Brushes.Black, new RectangleF(0, 0, sz.Width, sz.Height), format);
e.Graphics.ResetTransform();

如果您将此代码放在标签的 OnPaint 事件中，它会显示四次旋转表单的标题.

If you put this code in label's OnPaint event, it would display your rotated form's title four times.

这篇关于C#中的旋转文本对齐的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持编程学习网！