.NET Framework 4.6 and 4.5
Clears the value of the Password property.
The value of the Password property is Empty after a call to this method.
The following example shows how to clear a PasswordBox with the Clear method.
PasswordBox pwdBox = new PasswordBox();
pwdBox.Password = "Open Sesame!";
// Clear any contents of the PasswordBox, as well as the value stored in the Password property.
Supported in: 4.6, 4.5, 4, 3.5, 3.0
.NET Framework Client Profile
Supported in: 4, 3.5 SP1