Oak_3260548 Oak_3260548 - 11 months ago 70
Vb.net Question

Column Chart - Set string labels for X axis

This must be trivial, but I cannot find anything on the net.

I have a simple datatable dtChart with 3 columns (string, int32, int32) attached as datasource to Chart1 (to a two series) and set the ints for YValueMembers. The chart displays well, so far so good, but some scale numbers bellow columns.

Chart1.ChartAreas(0).AxisX.LabelStyle.Interval = 1

Displays labels on all columns, but with zeros.
When I try to set XValueMember to the first string column from dtCharts (either 1 or both series):

Chart1.Series(0).XValueMember = "ProcesName"

... then the painting of chart faisl (red rectangle with cross appears)
I tried this too:

Chart1.Series(0).AxisLabel = "#VALX"

...with no progress.

How do I set labels for the X axis in a data-bound chart?

EDIT: By the way, I know I can go throu the points collection and set the labels separately for each of them, but I would consider that a workaround, not a solution. There must be a direct way to use bound column, a sort-of "DisplayMember".

Answer Source

Just drop a new chart control on the form and use such code to show data in the chart:

Private Sub Form1_Load(ByVal sender As Object, ByVal e As EventArgs) Handles MyBase.Load
    Me.Chart1.DataSource = GetData()

    Chart1.Series(0).XValueMember = "Name"
    Chart1.Series(0).YValueMembers = "Math"
    Chart1.Series(0).IsValueShownAsLabel = True
    Chart1.ChartAreas(0).AxisX.LabelStyle.Angle = -90

    Chart1.Series(1).XValueMember = "Name"
    Chart1.Series(1).YValueMembers = "Physics"
    Chart1.Series(1).IsValueShownAsLabel = True
End Sub

Public Function GetData() As DataTable
    Dim dt = New DataTable()
    dt.Columns.Add("Name", GetType(String))
    dt.Columns.Add("Math", GetType(Integer))
    dt.Columns.Add("Physics", GetType(Integer))
    dt.Rows.Add("Alex", 12, 17)
    dt.Rows.Add("Richard", 19, 20)
    dt.Rows.Add("Alice", 14, 16)
    Return dt
End Function

And the result would be this chart:

enter image description here