MainWindow.xaml

<Window
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:SettingDate"
        xmlns:syncfusion="http://schemas.syncfusion.com/wpf"
        xmlns:skin="clr-namespace:Syncfusion.SfSkinManager;assembly=Syncfusion.SfSkinManager.WPF"
        skin:SfSkinManager.VisualStyle="Office2016Colorful"
        x:Class="SettingDate.MainWindow"
        mc:Ignorable="d" WindowStartupLocation="CenterScreen"
        Title="DateTimeEdit" Height="450" Width="600">
    <Grid x:Name="grid">
        <!--Setting date -->
        <syncfusion:DateTimeEdit x:Name="dateTimeEdit"
                                 Height="25" 
                                 Width="200"
                                 DateTime="07/05/2010"
                                 Pattern="LongDate"/>
    </Grid>
</Window>