这个问题的简单答案是改变Label的DOCK属性。默认为“NONE”。

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

使用System.Windows.Forms.LinkLabel代替Label，并设置属性LinkArea如下所示。

myLabel.LinkArea = new LinkArea(0, 0);

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;

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。

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>