here is some code you can use to achieve this.  unfortunately, you are constrained to using <ITEM_LABEL> for all tooltips in this example.  if you want to request this as an official feature of winchart then please visit this page: https://es.infragistics.com/community/ideas

using

System;

using

Infragistics.Win.UltraWinChart;

using

System.Windows.Forms;

using

Infragistics.UltraChart.Resources.Appearance;

using

Infragistics.UltraChart.Shared.Styles;

using

System.Drawing;

using

Infragistics.UltraChart.Shared.Events;

using

Infragistics.UltraChart.Core.Primitives;

using

System.Collections;

using

Infragistics.UltraChart.Resources;namespace TooltipXAxisLabels

{

public partial class Form1 : Form

{

private UltraChart UltraChart1 { get; set; }public Form1()

{

// add a chart to the formthis.UltraChart1 = new UltraChart();

this.UltraChart1.Dock = DockStyle.Fill;this.Controls.Add(this.UltraChart1);

// bind it to some series data with extra-long item labels.NumericSeries series1 = new NumericSeries();

series1.Points.Add(

new NumericDataPoint(1.0, "Point A AAAAAAAAAAAAAAAAA", false));series1.Points.Add(new NumericDataPoint(2.0, "Point B BBBBBBBBBBBBBBBBB", false));

series1.Points.Add(

new NumericDataPoint(3.0, "Point C CCCCCCCCCCCCCCCCC", false));series1.Points.Add(new NumericDataPoint(4.0, "Point D DDDDDDDDDDDDDDDDD", false));

this.UltraChart1.Series.Add(series1);

// configure x axis labelsthis.UltraChart1.Axis.X.Labels.Orientation = TextOrientation.Horizontal;

this.UltraChart1.Axis.X.Labels.SeriesLabels.Visible = false;

// add a text clipping behaviorthis.UltraChart1.Axis.X.Labels.Layout.Behavior = AxisLabelLayoutBehaviors.UseCollection;

ClipTextAxisLabelLayoutBehavior clipper = new ClipTextAxisLabelLayoutBehavior();clipper.ClipText = true;

clipper.Enabled =

true;clipper.EnableRollback = false;

clipper.HideText =

true;clipper.Trimming = StringTrimming.EllipsisCharacter;

this.UltraChart1.Axis.X.Labels.Layout.BehaviorCollection.Add(clipper);

// handle the chartdrawitem eventthis.UltraChart1.ChartDrawItem += new Infragistics.UltraChart.Shared.Events.ChartDrawItemEventHandler(UltraChart1_ChartDrawItem);

// the tooltips must use this format for the sample to work properlythis.UltraChart1.Tooltips.FormatString = "<ITEM_LABEL>";

}

private void UltraChart1_ChartDrawItem(object sender, ChartDrawItemEventArgs e)

{

Text textPrim = e.Primitive as Text;

// check if the primitive is a Text primitive.if (textPrim != null)

{

// this is the code you can use to make any primitive show tooltips.textPrim.Caps = PCaps.HitTest | PCaps.Tooltip;

textPrim.Chart =

this.UltraChart1.ChartType;textPrim.Row = Math.Max(textPrim.Row, 0);textPrim.Column = Math.Max(textPrim.Column, 0);

}

}

}

}