[. NET] Implementation in WPF TextBox can only enter numbers

Title, there are many ways to do this, and if you are using the development mode of MVVM, how do you implement this feature? As simple as creating a new attached property for a textbox, this problem can be solved perfectly.

Create a new Attachment property, Isonlyacceptfigure, and add the property callback function to it.

The code is as follows:

namespaceWPF. validation{ Public classTextboxonlyacceptfigurebehavior { Public Static ReadOnlyDependencyProperty Isonlyacceptfigureproperty =dependencyproperty.registerattached ("isonlyacceptfigure",typeof(BOOL),                typeof(Textboxonlyacceptfigurebehavior),NewUIPropertyMetadata (false, onbindedpasswordchanged));  Public Static BOOLgetisonlyacceptfigure (DependencyObject obj) {return(BOOL) obj.        GetValue (Isonlyacceptfigureproperty); }         Public Static voidSetisonlyacceptfigure (DependencyObject obj,BOOLvalue) {obj.        SetValue (isonlyacceptfigureproperty, value); }        Private Static voidonbindedpasswordchanged (DependencyObject obj, DependencyPropertyChangedEventArgs e) {
    varTextBox = obj asTextBox; if(TextBox = =NULL)                return; if((BOOL) {e.newvalue) {textbox.previewtextinput+=Textbox_previewtextinput; Textbox.previewkeydown+=Textbox_previewkeydown;            Dataobject.addpastinghandler (TextBox, textbox_pasting); }            Else{textbox.previewtextinput-=Textbox_previewtextinput; Textbox.previewkeydown-=Textbox_previewkeydown;            Dataobject.removepastinghandler (TextBox, textbox_pasting); }        }        Private Static voidTextbox_pasting (Objectsender, Dataobjectpastingeventargs e) {            if(E.dataobject.getdatapresent (typeof(string)))            {                varText = (string) E.dataobject.getdata (typeof(string)); if(!isnumberic (text))                {E.cancelcommand (); }            }            Else{E.cancelcommand (); }        }        Private Static voidTextbox_previewkeydown (Objectsender, KeyEventArgs e) {            if(E.key = =key.space) e.handled=true; }        Private Static voidTextbox_previewtextinput (Objectsender, TextCompositionEventArgs e) {e.handled= !isnumberic (E.text); }         Public Static BOOLIsnumberic (string_string) {            if(string. IsNullOrEmpty (_string))return false; return_string. All (Char.        IsDigit); }    }}

How to Invoke:

<textbox local:textboxonlyacceptfigurebehavior.isonlyacceptfigure="True"/>

PS: Verify that the input code comes from the network, again thanks to the user to share.

I wish you a happy life!

[. NET] Implementation in WPF TextBox can only enter numbers