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    <head><title>Automatic Properties</title>
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        <p class="MCWebHelpFramesetLink" style="display: none;"><a href="../../index_CSH.html#platform_specific_issues/automatic_properties.htm" style="">Open topic with navigation</a>
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        <h1><a name="kanchor108"></a>Automatic Properties</h1>
        <p>Automatic
properties simply allow a user to skip the step of introducing private field
variables when the property simply sets and gets the field value:</p>
        <div class="codesnippet" MadCap:conditions="Primary.c#">
            <pre class="prettyprint" xml:space="preserve">class Person
{
    public string Name { get; set; }
}</pre>
            <div class="codesnippet-meta">AutoProperties.cs: Auto property
			<div class="codedownload"><a href="../CodeExamples/platform/autoproperties/Example-platform-autoproperties-csharp.zip" class="codedownload" MadCap:conditions="Primary.Online">Download Code</a></div><div class="codedownload copylink-marker" MadCap:conditions="Primary.Online"><a href="#copy">Copy Code</a></div></div>
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        <div class="codesnippet" MadCap:conditions="Primary.VB.NET">
            <pre class="prettyprint lang-vb" MadCap:conditions="Primary.Online" xml:space="preserve">Public Class Person
    Public Property Name() As String
End Class</pre>
            <div class="codesnippet-meta">AutoProperties.vb: Auto property
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        <p class="">Behind the scenes the compiler creates a field and the regular property code. The field-name depends on the compiler. For C# the field-name of auto-property is <span class="method">&lt;PropertyName&gt;k__BackingField</span>. For example the property FirstName will be stored in the field <span class="method">&lt;FirstName&gt;k__BackingField</span>. For <a href="http://msdn.microsoft.com/en-us/library/dd293589.aspx" target="_parent">VB.Net the field-name of auto-property</a> is <span class="method">_PropertyName</span>.  For example the property FirstName will be stored in the field <span class="method">_FirstName</span>.</p>
        <div class="codesnippet" MadCap:conditions="Primary.c#">
            <pre class="prettyprint" xml:space="preserve">public class Person
{
    // the name is actually &lt;Name&gt;k__BackingField 
    // but you cannot express that in C# code
    private string name;

    public string Name
    {
        get { return name; }
        set { name = value; }
    }
}</pre>
            <div class="codesnippet-meta">AutoProperties.cs: Auto property behind the scenes
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        <div class="codesnippet" MadCap:conditions="Primary.VB.NET">
            <pre class="prettyprint lang-vb" MadCap:conditions="Primary.Online" xml:space="preserve">Public Class Person
    Private _Name As String

    Public Property Name() As String
        Get
            Return _Name
        End Get
        Set(ByVal value As String)
            _Name = value
        End Set
    End Property
End Class</pre>
            <div class="codesnippet-meta">AutoProperties.vb: Auto property behind the scenes
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        <h2>Issues With Auto Properties</h2>
        <p>Note that db4o always uses the field name for its configuration. This also applies to auto-properties. You need to use the field-name to specify index etc. </p>
        <p>For C# the name of the backing field is not specified and a compiler implementation detail. Therefore it's possible that it actually changes in the future.</p>
        <p>For example to index the auto property Name:</p>
        <div class="codesnippet" MadCap:conditions="Primary.c#">
            <pre class="prettyprint" xml:space="preserve">IEmbeddedConfiguration configuration = Db4oEmbedded.NewConfiguration();
configuration.Common.ObjectClass(typeof(Person)).ObjectField("&lt;Name&gt;k__BackingField").Indexed(true);</pre>
            <div class="codesnippet-meta">AutoProperties.cs: Configure auto properties
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        <div class="codesnippet" MadCap:conditions="Primary.VB.NET">
            <pre class="prettyprint lang-vb" MadCap:conditions="Primary.Online" xml:space="preserve">Dim configuration As IEmbeddedConfiguration = Db4oEmbedded.NewConfiguration()
configuration.Common.ObjectClass(GetType(Person)).ObjectField("_Name").Indexed(True)</pre>
            <div class="codesnippet-meta">AutoProperties.vb: Configure auto properties
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