# V3046. WPF: the type registered for DependencyProperty does not correspond with the type of the property used to access it.

The analyzer detected a possible error related to dependency property registration. When registering a dependency property, a wrong type was specified for its values.

In the following example, it is property CurrentTimeProperty:

    class A : DependencyObject
    {
    public static readonly DependencyProperty CurrentTimeProperty =
      DependencyProperty.Register("CurrentTime", typeof(int),....);

    public DateTime CurrentTime
    {
        get { return (DateTime)GetValue(CurrentTimeProperty); }
        set { SetValue(CurrentTimeProperty, value); }
    }
    ....

Because of using copy-paste when registering the dependency property, type int was mistakenly specified as the type of values taken by the property. Trying to write into or read from CurrentTimeProperty within the CurrentTime property will raise an error.

A correct way to register the dependency property in the code above is as follows:

    public static readonly DependencyProperty CurrentTimeProperty =
      DependencyProperty.Register("CurrentTime", typeof(DateTime),....);

This diagnostic also checks if the type of a dependency property being registered and the type of its default value correspond with each other.

    public static readonly DependencyProperty CurrentTimeProperty =
      DependencyProperty.Register("CurrentTime", typeof(DateTime),
                                  typeof(A),
                                  new FrameworkPropertyMetadata(132));

In this example, the default value is 132 while type DateTime is specified as the type of values that the property can take.

You can look at examples of errors detected by the V3046 diagnostic.