Use Wild-Card Patterns in Selection Set Filter Criteria (.NET)

Symbol names and strings in selection filters can include wild-card patterns.

The following table identifies the wild-card characters recognized by AutoCAD, and what each means in the context of a string:

Wild-card characters
Character	Definition
# (pound)	Matches any single numeric digit
@ (at)	Matches any single alphabetic character
. (period)	Matches any single non-alphanumeric character
* (asterisk)	Matches any character sequence, including an empty one, and it can be used anywhere in the search pattern: at the beginning, middle, or end
? (question mark)	Matches any single character
~ (tilde)	If it is the first character in the pattern, it matches anything except the pattern
[...]	Matches any one of the characters enclosed
[~...]	Matches any single character not enclosed
- (hyphen)	Used inside brackets to specify a range for a single character
, (comma)	Separates two patterns
` (reverse quote)	Escapes special characters (reads next character literally)

Use a reverse quote (`) to indicate that a character is not a wildcard, but is to be taken literally. For example, to specify that only an anonymous block named “*U2” be included in the selection set, use the value“`*U2”.

Select MText where a specific word appears in the text

The following example defines a selection filter that selects MText objects that contain the text string of “The”.

C# Example

using Autodesk.AutoCAD.Runtime;
using Autodesk.AutoCAD.ApplicationServices;
using Autodesk.AutoCAD.DatabaseServices;
using Autodesk.AutoCAD.EditorInput;
 
[CommandMethod("FilterMtextWildcard")]
public static void FilterMtextWildcard()
{
    // Get the current document editor
    Editor acDocEd = Application.DocumentManager.MdiActiveDocument.Editor;

    // Create a TypedValue array to define the filter criteria
    TypedValue[] acTypValAr = new TypedValue[2];
    acTypValAr.SetValue(new TypedValue((int)DxfCode.Start, "MTEXT"), 0);
    acTypValAr.SetValue(new TypedValue((int)DxfCode.Text, "*The*"), 1);

    // Assign the filter criteria to a SelectionFilter object
    SelectionFilter acSelFtr = new SelectionFilter(acTypValAr);

    // Request for objects to be selected in the drawing area
    PromptSelectionResult acSSPrompt;
    acSSPrompt = acDocEd.GetSelection(acSelFtr);

    // If the prompt status is OK, objects were selected
    if (acSSPrompt.Status == PromptStatus.OK)
    {
        SelectionSet acSSet = acSSPrompt.Value;

        Application.ShowAlertDialog("Number of objects selected: " +
                                    acSSet.Count.ToString());
    }
    else
    {
        Application.ShowAlertDialog("Number of objects selected: 0");
    }
}