C# 如何使用interop COM在autocad中更改块参照的颜色

我无法更改acadblock的颜色。但我可以改变线条和圆弧等的颜色，但当我尝试改变块颜色时，它不会改变。有人能告诉我怎么做吗

这里我提到了我的代码：

        AcadApplication acadApp;
        AcadDocument curDoc;
        AcadSelectionSet selset;
        AcadLine lin;
        AcadBlockReference blkRef;
        short[] ftype = new short[1];
        object[] fdata = new object[1];
        ftype[0] = 0;
        fdata[0] = "Line,INSERT";

        acadApp = (AcadApplication)Marshal.GetActiveObject("Autocad.Application.18");
        curDoc = acadApp.ActiveDocument;
        selset = curDoc.SelectionSets.Add("Selset2");
        selset.Select(AcSelect.acSelectionSetAll, null, null, ftype, fdata);
        foreach (AcadEntity item in selset)
        {
            if (item.ObjectName == "AcDbLine")
            {
                item.color = ACAD_COLOR.acYellow;  //here working fine

            }
            else if (item.ObjectName == "AcDbBlockReference")
            {
                item.color = ACAD_COLOR.acMagenta;  //here does not working

            }
        }
        selset.Delete();

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提前感谢。

您需要使用AcadApplication作为颜色对象工厂来创建和分配颜色

const string dwgPath = @"C:\Test.dwg";
var acadDoc = acadDocs.Open(dwgPath);

foreach (AcadEntity ent in acadDoc.ModelSpace)
{
    var block = ent as AcadBlockReference;
    if (block == null) continue;
    {
        if (!block.Name.Equals("BlockName", StringComparison.CurrentCultureIgnoreCase)) continue;

        var newColor = acadApp.GetInterfaceObject("AutoCAD.AcCmColor.18") as AcadAcCmColor;
        if (newColor != null)
        {
            newColor.ColorIndex = AcColor.acMagenta;
            block.TrueColor = newColor;
        }
    }
}

---

请注意，注册的AcCmColor类必须与您加载的AutoCAD interop库相匹配。

谢谢Locke先生。。它只工作部分块，而另一些块不工作。如果在我创建块图形之前，将“颜色”设置为“byBlock”意味着“创建块”可以更改颜色，并且工作正常。否则它就不起作用了。。。