EPPlus ColumnStacked图表数据点颜色 [英] EPPlus ColumnStacked chart data point colors

问题描述

我能够用EPPlus生成列堆叠图。还有就是是要求改变数据点的颜色。

I am able to generate Column Stacked chart using EPPlus. There is is requirement to change the color of datapoint.

我发现在的输入链接的描述在这里但它只是改变了系列第一数据点的颜色。我可以得到帮助更改其他数据点的颜色为好。这里是我要找在这里输入的形象描述

I found the solution of at enter link description here but it only changes the color of first datapoint of the series. Can I get help to change the color of other datapoints as well. Here is the concept that I am looking for enter image description here

下面是有助于改变数据点第一色功能

Here is the function that helps to change datapoint first color

    public void SetDataPointStyle(OfficeOpenXml.Drawing.Chart.ExcelChart chart, ExcelChartSerie series, int totalDataPoint, Color color)
{
    var i = 0;
    var found = false;
    foreach (var s in chart.Series)
    {
        if (s == series)
        {
            found = true;
            break;
        }
        ++i;
    }
    if (!found) throw new InvalidOperationException("series not found.");

    var nsm = chart.WorkSheet.Drawings.NameSpaceManager;
    var nschart = nsm.LookupNamespace("c");
    var nsa = nsm.LookupNamespace("a");
    var node = chart.ChartXml.SelectSingleNode(@"c:chartSpace/c:chart/c:plotArea/c:barChart/c:ser[c:idx[@val='" + i.ToString(System.Globalization.CultureInfo.InvariantCulture) + "']]", nsm);
    var doc = chart.ChartXml;

    var spPr = doc.CreateElement("c:spPr", nschart);
    var solidFill = spPr.AppendChild(doc.CreateElement("a:solidFill", nsa));
    var srgbClr = solidFill.AppendChild(doc.CreateElement("a:srgbClr", nsa));
    var valattrib = srgbClr.Attributes.Append(doc.CreateAttribute("val"));
    valattrib.Value = ToHex(color).Substring(1);

    //var ln = spPr.AppendChild(doc.CreateElement("a:ln", nsa));
    //var lnSolidFill = ln.AppendChild(doc.CreateElement("a:solidFill", nsa));
    //var lnSrgbClr = lnSolidFill.AppendChild(doc.CreateElement("a:srgbClr", nsa));
    //var lnValattrib = lnSrgbClr.Attributes.Append(doc.CreateAttribute("val"));
    //lnValattrib.Value = ToHex(Color.Gray).Substring(1);

    node.AppendChild(spPr);
}
public String ToHex(Color c)
{
    return "#" + c.R.ToString("X2") + c.G.ToString("X2") + c.B.ToString("X2");
}

SetDataPointStyle（图表，chart.Series [0]，1，Color.Tan）;

SetDataPointStyle(chart, chart.Series[0], 1, Color.Tan);

推荐答案

您必须填充一系列每个系列的数据点的颜色。此处是将在一系列的数据点设置为随机颜色扩展方法。只要有指定数量意甲。如果选择你自己的颜色只是重写逻辑或数组发送到使用：

You have to populate a series of data point colors per series. Here is an extension method that will set the series data points to random colors. Just have to specify the serie number. If pick your own colors just override the logic or send in an array to use:

public static void SetChartPointRandomColors(this ExcelChart chart, int serieNumber)
{
    var chartXml = chart.ChartXml;

    var nsa = chart.WorkSheet.Drawings.NameSpaceManager.LookupNamespace("a");
    var nsuri = chartXml.DocumentElement.NamespaceURI;

    var nsm = new XmlNamespaceManager(chartXml.NameTable);
    nsm.AddNamespace("a", nsa);
    nsm.AddNamespace("c", nsuri);

    var serieNode = chart.ChartXml.SelectSingleNode(@"c:chartSpace/c:chart/c:plotArea/c:barChart/c:ser[c:idx[@val='" + serieNumber + "']]", nsm);
    var serie = chart.Series[serieNumber];
    var points = serie.Series.Length;
    var rand = new Random(serieNumber);

    for (var i = 1; i <= points; i++)
    {
        var dPt = chartXml.CreateNode(XmlNodeType.Element, "dPt", nsuri);
        var idx = chartXml.CreateNode(XmlNodeType.Element, "idx", nsuri);
        var att = chartXml.CreateAttribute("val", nsuri);
        att.Value = i.ToString();
        idx.Attributes.Append(att);
        dPt.AppendChild(idx);

        var srgbClr = chartXml.CreateNode(XmlNodeType.Element, "srgbClr", nsa);
        att = chartXml.CreateAttribute("val");

        //Generate a random color - override with own logic to specify
        var color = Color.FromArgb(rand.Next(256), rand.Next(256), rand.Next(256));
        att.Value = $"{color.R:X2}{color.G:X2}{color.B:X2}";
        srgbClr.Attributes.Append(att);

        var solidFill = chartXml.CreateNode(XmlNodeType.Element, "solidFill", nsa);
        solidFill.AppendChild(srgbClr);

        var spPr = chartXml.CreateNode(XmlNodeType.Element, "spPr", nsuri);
        spPr.AppendChild(solidFill);

        dPt.AppendChild(spPr);
        serieNode.AppendChild(dPt);
    }
}

下面是使用的一个示例：

Here is an example of usage:

[TestMethod]
public void Chart_BarChart_Colors_Test()
{
    //Throw in some data
    var datatable = new DataTable("tblData");
    datatable.Columns.AddRange(new[]{new DataColumn("Col1", typeof(int)),new DataColumn("Col2", typeof(int)),new DataColumn("Col3", typeof(int))});
    for (var i = 0; i < 10; i++){var row = datatable.NewRow();row[0] = i;row[1] = i * 10;row[2] = i * 15;datatable.Rows.Add(row);}

    //Create a test file    
    var fileInfo = new FileInfo(@"c:\temp\Chart_BarChart_Colors.xlsx");
    if (fileInfo.Exists)
        fileInfo.Delete();

    using (var pck = new ExcelPackage(fileInfo))
    {
        var workbook = pck.Workbook;
        var worksheet = workbook.Worksheets.Add("Sheet1");
        worksheet.Cells.LoadFromDataTable(datatable, true);

        var chart = worksheet.Drawings.AddChart("chart test", eChartType.ColumnStacked);
        chart.Series.Add(worksheet.Cells["B2:B11"], worksheet.Cells["A2:A11"]);
        chart.Series.Add(worksheet.Cells["C2:C11"], worksheet.Cells["A2:A11"]);

        chart.SetChartPointRandomColors(0);
        chart.SetChartPointRandomColors(1);

        pck.Save();
    }
}

会给你这样的：

这篇关于EPPlus ColumnStacked图表数据点颜色的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！