Use the WPF month calendar control to view dates by month.  

Calendar Control

Single Control for viewing dates on a month by month basis.
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Single/Multiple Date Selection

Supports the selection of single dates as well as contiguous or non-contiguous multiple dates.
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Use the WPF month calendar date selector to choose single or multiple dates in a calendar view.  
The Windows 7 style month calendar allows users to experience animation in viewing single or multiple dates.  

Windows 7 Style Calendar

Allows the calendar to animate and 'zoom in and out' visualizing dates ranging from a single day to decades.
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Fully Stylable Calendar Elements

A modular composition of calendar elements in XAML enables you to design the calendar's presentation with fine-grained customizability.
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Customize the presentation of calendar information using the WPF fully stylable calendar elements feature.