在标签中使用style="overflow:Scroll"，如下面的HTML。这将在面板内的标签中添加滚动条。

<asp:Label
    ID="txtAOI"
    runat="server"
    style="overflow:Scroll"
    CssClass="areatext"
    BackColor="White"
    BorderColor="Gray"
    BorderWidth="1"
    Width = "900" ></asp:Label>

If your panel is limiting the width of your label, you can set your label’s Anchor property to Left, Right and set AutoSize to true. This is conceptually similar to listening for the Panel’s SizeChanged event and updating the label’s MaximumSize to a new Size(((Control)sender).Size.Width, 0) as suggested by a previous answer. Every side listed in the Anchor property is, well, anchored to the containing Control’s respective inner side. So listing two opposite sides in Anchor effectively sets the control’s dimension. Anchoring to Left and Right sets the Control’s Width property and Anchoring to Top and Bottom would set its Height property.

这个解决方案，作为c#:

label.Anchor = AnchorStyles.Left | AnchorStyles.Right;
label.AutoSize = true;

事实上，公认的答案是不必要的复杂。

如果您将标签设置为“自动大小”，它将随着您放入的任何文本而自动增长。(这包括垂直增长。)

如果你想让它以特定的宽度换行，你可以设置MaximumSize属性。

myLabel.MaximumSize = new Size(100, 0);
myLabel.AutoSize = true;

测试和工作。

根据@hypo的回答有更好的答案吗

public class GrowLabel : Label {
    private bool mGrowing;
    public GrowLabel() {
        this.AutoSize = false;
    }
    private void resizeLabel() {
        if (mGrowing)
            return;
        try {
            mGrowing = true;
            int width = this.Parent == null ? this.Width : this.Parent.Width;

            Size sz = new Size(this.Width, Int32.MaxValue);
            sz = TextRenderer.MeasureText(this.Text, this.Font, sz, TextFormatFlags.WordBreak);
            this.Height = sz.Height + Padding.Bottom + Padding.Top;
        } finally {
            mGrowing = false;
        }
    }
    protected override void OnTextChanged(EventArgs e) {
        base.OnTextChanged(e);
        resizeLabel();
    }
    protected override void OnFontChanged(EventArgs e) {
        base.OnFontChanged(e);
        resizeLabel();
    }
    protected override void OnSizeChanged(EventArgs e) {
        base.OnSizeChanged(e);
        resizeLabel();
    }
}

Int width = this。Parent == null ?这一点。宽度:this.Parent.Width;这允许你使用自动增长标签时停靠到一个父，例如一个面板。

这一点。高度= sz。高度+填充。Bottom + Padding.Top;这里我们关心顶部和底部的填充。

设置AutoEllipsis属性为“TRUE”，AutoSize属性为“FALSE”。

我必须找到一个快速的解决方案，所以我只是使用了一个具有这些属性的文本框:

var myLabel = new TextBox
                    {
                        Text = "xxx xxx xxx",
                        WordWrap = true,
                        AutoSize = false,
                        Enabled = false,
                        Size = new Size(60, 30),
                        BorderStyle = BorderStyle.None,
                        Multiline =  true,
                        BackColor =  container.BackColor
                    };