olep/MainWindow.xaml

<Window x:Class="WPF_Entity_Examole.MainWindow"
        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:WPF_Entity_Examole"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="800">
    <Grid>
        <DataGrid x:Name="dgogrenci" HorizontalAlignment="Left" Height="185" Margin="218,49,0,0" VerticalAlignment="Top" Width="246" Loaded="Dgogrenci_Loaded" />
        <TextBox x:Name="txtId" HorizontalAlignment="Left" Height="23" Margin="577,59,0,0" TextWrapping="Wrap" VerticalAlignment="Top" Width="120"/>
        <TextBox x:Name="txtFist" HorizontalAlignment="Left" Height="23" Margin="577,91,0,0" TextWrapping="Wrap" VerticalAlignment="Top" Width="120"/>
        <TextBox x:Name="txtLast" HorizontalAlignment="Left" Height="23" Margin="577,125,0,0" TextWrapping="Wrap" VerticalAlignment="Top" Width="120"/>
        <Button x:Name="InsertClick" Content="Insert" HorizontalAlignment="Left" Margin="594,164,0,0" VerticalAlignment="Top" Width="75" Click="InsertClick_Click" />
        <Button x:Name="DeleteClick" Content="Delete" HorizontalAlignment="Left" Margin="594,190,0,0" VerticalAlignment="Top" Width="75" Click="DeleteClick_Click" />
        <Button x:Name="UpdateClick" Content="Update" HorizontalAlignment="Left" Margin="594,216,0,0" VerticalAlignment="Top" Width="75" Click="UpdateClick_Click" />
        <Label x:Name="label" Content="ID" HorizontalAlignment="Left" Margin="496,57,0,0" VerticalAlignment="Top"/>
        <Label x:Name="label1" Content="First Name" HorizontalAlignment="Left" Margin="496,93,0,0" VerticalAlignment="Top"/>
        <Label x:Name="label2" Content="Last Name" HorizontalAlignment="Left" Margin="496,126,0,0" VerticalAlignment="Top"/>

    </Grid>
</Window>