radzen-blazor/RadzenBlazorDemos/Pages/SpiderChartValueFormat.razor

<RadzenStack class="rz-p-0 rz-p-md-6 rz-p-lg-12">
    <RadzenCard Variant="Variant.Outlined">
        <RadzenStack Orientation="Orientation.Horizontal" AlignItems="AlignItems.Center" Wrap="FlexWrap.Wrap">
            <RadzenStack Gap="0.25rem">
                <RadzenText TextStyle="TextStyle.Caption">Value Format</RadzenText>
                <RadzenSelectBar @bind-Value="valueFormat" TValue="string" Size="ButtonSize.Small" Change="@(() => StateHasChanged())">
                    <Items>
                        <RadzenSelectBarItem Text="Percent" Value="@("percent")" />
                        <RadzenSelectBarItem Text="Number" Value="@("number")" />
                        <RadzenSelectBarItem Text="Score" Value="@("score")" />
                        <RadzenSelectBarItem Text="Currency" Value="@("currency")" />
                    </Items>
                </RadzenSelectBar>
            </RadzenStack>
        </RadzenStack>
    </RadzenCard>

    <RadzenSpiderChart Style="width: 100%; height: 500px;">
    <RadzenSpiderSeries TItem="SkillData"
                        Data="@aliceData"
                        CategoryProperty="@nameof(SkillData.Skill)"
                        ValueProperty="@nameof(SkillData.Score)"
                        Title="Alice"
                        ValueFormatter="@GetValueFormatter()" />
    <RadzenSpiderSeries TItem="SkillData"
                        Data="@bobData"
                        CategoryProperty="@nameof(SkillData.Skill)"
                        ValueProperty="@nameof(SkillData.Score)"
                        Title="Bob"
                        ValueFormatter="@GetValueFormatter()" />
    </RadzenSpiderChart>
</RadzenStack>

@code {
    string valueFormat = "percent";

    Func<double, string> GetValueFormatter()
    {
        return valueFormat switch
        {
            "percent" => (value) => $"{value:F0}%",
            "number" => (value) => value.ToString("F1"),
            "score" => (value) => $"{value:F0}/100",
            "currency" => (value) => $"${value:F0}",
            _ => (value) => value.ToString("F1")
        };
    }

    class SkillData
    {
        public string Skill { get; set; }
        public double Score { get; set; }
    }

    IEnumerable<SkillData> aliceData = new SkillData[]
    {
        new SkillData { Skill = "Communication", Score = 90 },
        new SkillData { Skill = "Problem Solving", Score = 85 },
        new SkillData { Skill = "Teamwork", Score = 92 },
        new SkillData { Skill = "Leadership", Score = 78 },
        new SkillData { Skill = "Creativity", Score = 88 },
    };

    IEnumerable<SkillData> bobData = new SkillData[]
    {
        new SkillData { Skill = "Communication", Score = 75 },
        new SkillData { Skill = "Problem Solving", Score = 92 },
        new SkillData { Skill = "Teamwork", Score = 80 },
        new SkillData { Skill = "Leadership", Score = 88 },
        new SkillData { Skill = "Creativity", Score = 70 },
    };
}