Specify Both X And Y

sample image

View model

using CommunityToolkit.Mvvm.ComponentModel;
using LiveChartsCore;
using LiveChartsCore.Defaults;
using LiveChartsCore.SkiaSharpView;

namespace ViewModelsSamples.Lines.XY;

public partial class ViewModel : ObservableObject
{
    public ISeries[] Series { get; set; } =
    {
        new LineSeries<ObservablePoint>
        {
            Values = new ObservablePoint[]
            {
                new ObservablePoint(0, 4),
                new ObservablePoint(1, 3),
                new ObservablePoint(3, 8),
                new ObservablePoint(18, 6),
                new ObservablePoint(20, 12)
            }
        }
    };
}

HTML

@page "/Lines/XY"
@using LiveChartsCore.SkiaSharpView.Blazor
@using ViewModelsSamples.Lines.XY

<CartesianChart Series="ViewModel.Series"/>

@code {
	public ViewModel ViewModel { get; set; } = new();
}

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Cartesian chart control
Line series properties