comboBox from enum?
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From: DanB on 7 Mar 2010 14:38 Say I want to add a comboBox to a form and have it populated with the enum of an object. Is there a way to do this quickly? I've been creating the list by hand. Thanks, Dan. Like for Markers: namespace System.Windows.Forms.DataVisualization.Charting { // Summary: // Specifies a style for markers. public enum MarkerStyle { // Summary: // No marker is displayed for the series or data point. None = 0, // // Summary: // A square marker is displayed. Square = 1, // // Summary: // A circular marker is displayed. Circle = 2, // // Summary: // A diamond-shaped marker is displayed. Diamond = 3, // // Summary: // A triangular marker is displayed. Triangle = 4, // // Summary: // A cross-shaped marker is displayed. Cross = 5, // // Summary: // A 4-point star-shaped marker is displayed. Star4 = 6, // // Summary: // A 5-point star-shaped marker is displayed. Star5 = 7, // // Summary: // A 6-point star-shaped marker is displayed. Star6 = 8, // // Summary: // A 10-point star-shaped marker is displayed. Star10 = 9, } }
From: Peter Duniho on 7 Mar 2010 17:07 DanB wrote: > > Say I want to add a comboBox to a form and have it populated with the > enum of an object. Is there a way to do this quickly? I've been creating > the list by hand. What does "enum of an object" mean? Do you actually mean "values of an enum"? If so, this might work for you: static void AddEnumValues<T>(this ComboBox combo) { combo.Items.AddRange( Enum.GetValues(typeof(T)).Cast<object>().ToArray()); } used like this (extension method syntax): comboBox1.AddEnumValues<MarkerStyle>(); or if you don't use the extension method syntax (assuming the method is in a class named "Util"): Util.AddEnumValues<MarkerStyle>(comboBox1); Pete
From: DanB on 7 Mar 2010 18:17 Peter Duniho wrote: > DanB wrote: >> >> Say I want to add a comboBox to a form and have it populated with the >> enum of an object. Is there a way to do this quickly? I've been >> creating the list by hand. > > What does "enum of an object" mean? Do you actually mean "values of an > enum"? Thanks Peter, I meant the 'names' of the numeration. And at 'writing' time. Yes I see I can get the names at run time. I do that to look up the string name in the enum to get the value now. I'm doing this kind of stuff: To box: tname= Enum.GetName( typeof( SeriesChartType ), curItem.seriesSet[ pos ].type ); comboBoxChartType1.SelectedIndex= comboBoxChartType.FindStringExact( tname );; From box: curItem.seriesSet[ pos ].type= (SeriesChartType)Enum.Parse( typeof(SeriesChartType), comboBoxChartType.Text, true ); And because my .type is of type SeriesChartType, it parses out to the xml by name without the need of my creating an interface, I like that. This is way different thinking than in c++, I'm still in the deep learning curve. Best, Dan.
From: Peter Duniho on 7 Mar 2010 18:27 DanB wrote: > [...] > To box: > tname= Enum.GetName( typeof( SeriesChartType ), curItem.seriesSet[ pos > ].type ); > comboBoxChartType1.SelectedIndex= comboBoxChartType.FindStringExact( > tname );; If you initialize the items in the ComboBox to the actual enum values (e.g. as in the code I posted earlier), then you can simply set the SelectedItem property to the enum value in question. The ComboBox class will handle the rest, without you having to explicitly call something like FindStringExact(). So, when the ComboBox is properly initialized, you get something more like this for the above code: comboBoxChartType1.SelectedItem = cutItem.seriesSet[pos].type; Likewise, this: > From box: > curItem.seriesSet[ pos ].type= (SeriesChartType)Enum.Parse( > typeof(SeriesChartType), comboBoxChartType.Text, true ); �becomes this: curItem.seriesSet[pos].type = (SeriesChartType)comboBoxChartType1.SelectedItem; Pete
From: DanB on 7 Mar 2010 20:35
Peter Duniho wrote: > > If you initialize the items in the ComboBox to the actual enum values > (e.g. as in the code I posted earlier), then you can simply set the > SelectedItem property to the enum value in question. The ComboBox class > will handle the rest, without you having to explicitly call something > like FindStringExact(). > > So, when the ComboBox is properly initialized, you get something more > like this for the above code: > > comboBoxChartType1.SelectedItem = cutItem.seriesSet[pos].type; > > Likewise, this: > >> From box: >> curItem.seriesSet[ pos ].type= (SeriesChartType)Enum.Parse( >> typeof(SeriesChartType), comboBoxChartType.Text, true ); > > �becomes this: > > curItem.seriesSet[pos].type = > (SeriesChartType)comboBoxChartType1.SelectedItem; Hi Peter, Old habits. I would avoid storing data as an index whenever possible. Now my 'type' would be a plain old int rather than a type with appropriate baggage. What if there were a revision and a new name where put in at position 3? If stored by name versioning is automatic. I can change the order in my combo, add delete stuff without maintinance of the database. But then I see that XmlSerialize is rather non forgiving. My xml lib doesn't care if stuff comes and goes. I have not had to version my product xml databases ever for small structural changes, additions, deletions. In fact, if I don't explicitly delete and rewrite a set of elements, legacy elements will ride along forever. Where as one little thing out of place and XmlSerialize completly fails on me. It doesn't return any of my data. It means I'll have to run a backup utility and preserve/reload if a read fails I guess. Here is a snip from one database: <VirtualFileTable> <VirtualItem> <vName>DEFAULT_PROJECT_NAME</vName> <path>Default.ars</path> <flags>SYSTEM,PERMANENT,EXFROMREPORT</flags> .... The flags are an enum in the program and I can mess with it anytime I'd like without affecting previous use. Best, Dan. |