Password box password cannot bind problem solution

When you want to extend the control, you find that PasswordBox is a sealed class and is not inheritable.

This function is implemented by attaching properties.

Two additional properties declared

ispasswordbindingenabled: Used to indicate whether a password can be used for binding, a subscription when a value changes, or a unsubscribe when password changes the password attached property for the binding

bindedpassword: The password used for binding, synchronized with the password, when the value change is synchronized with password

 /// <summary>    ///Extended Password box password can be used for binding helper classes/// </summary>     Public classBindedpasswordhelper {#regionAdditional property that indicates whether the password for the password box can be bound Public Static BOOLgetispasswordbindingenabled (DependencyObject obj) {return(BOOL) obj.        GetValue (Ispasswordbindingenabledproperty); }         Public Static voidsetispasswordbindingenabled (DependencyObject obj,BOOLvalue) {obj.        SetValue (ispasswordbindingenabledproperty, value); }         Public Static ReadOnlyDependencyProperty Ispasswordbindingenabledproperty =dependencyproperty.registerattached ("ispasswordbindingenabled",typeof(BOOL),            typeof(bindedpasswordhelper),NewUIPropertyMetadata (false, onispasswordbindingenabledchanged)); Private Static voidonispasswordbindingenabledchanged (DependencyObject obj, DependencyPropertyChangedEventArgs e) {varPasswordBox = obj asPasswordBox; if(PasswordBox! =NULL) {passwordbox.passwordchanged-=passwordboxpasswordchanged; if((BOOL) {e.newvalue) {passwordbox.passwordchanged+=passwordboxpasswordchanged; }            }        }        //update the password for binding when the password changes        Private Static voidPasswordboxpasswordchanged (Objectsender, RoutedEventArgs e) {            varPasswordBox =(PasswordBox) sender; if(!string. Equals (Getbindedpassword (PasswordBox), Passwordbox.password)) {Setbindedpassword (PasswordBox, p            Asswordbox.password); }        }        #endregion        #regionAdditional properties for the password to bind Public Static stringGetbindedpassword (DependencyObject obj) {return(string) obj.        GetValue (Bindedpasswordproperty); }         Public Static voidSetbindedpassword (DependencyObject obj,stringvalue) {obj.        SetValue (bindedpasswordproperty, value); }         Public Static ReadOnlyDependencyProperty Bindedpasswordproperty =dependencyproperty.registerattached ("Bindedpassword",typeof(string),            typeof(bindedpasswordhelper),NewUIPropertyMetadata (string.        Empty, onbindedpasswordchanged)); //update password when bound password is updated        Private Static voidonbindedpasswordchanged (DependencyObject obj, Dependencypropertych Angedeventargs e) {varPasswordBox = obj asPasswordBox; if(PasswordBox! =NULL) {Passwordbox.password= E.newvalue = =NULL?string.            Empty:e.newvalue.tostring (); }        }        #endregion    }

Using the method, it is important to note that, like a textbox, it is important to declare that mode is UpdateSourceTrigger, otherwise the bound value will not be synchronized with the Background property

    <Style= "{StaticResource Passwordboxstyle}"                             Helper: bindedpasswordhelper.ispasswordbindingenabled= "True"                             Helper: Bindedpasswordhelper.bindedpassword= "{Binding password,mode=twoway,updatesourcetrigger= PropertyChanged}"/>

Password box password cannot bind problem solution