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POWhy am I getting a "Nullable object must have a value" exception when I'm using Condition?
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  1. POWhy am I getting a "Nullable object must have a value" exception when I'm using Condition?
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    copied!<p>I'm getting a "Nullable object must have a value" in the example code below. Why do I need the following fix to make this work:</p> <pre><code>.ForMember(dest =&gt; dest.ShirtColor, dest =&gt; dest.MapFrom(src =&gt; src.ShirtColor != null ? new OptionSetValue((int) src.ShirtColor) : null)) </code></pre> <pre class="lang-cs prettyprint-override"><code>AutoMapper.Mapper.CreateMap&lt;PersonA, PersonB&gt;() .ForMember(dest =&gt; dest.FirstName, dest =&gt; dest.MapFrom(src =&gt; src.FirstName)) .ForMember(dest =&gt; dest.LastName, dest =&gt; dest.MapFrom(src =&gt; src.LastName)) // Condition to avoid overwriting existing data!!! .ForMember(dest =&gt; dest.ShirtColor, dest =&gt; dest.Condition(src =&gt; src.ShirtColor != null)) .ForMember(dest =&gt; dest.ShirtColor, dest =&gt; dest.MapFrom( src =&gt; new OptionSetValue((int)src.ShirtColor))) // Fix that should not be needed due to condition: //.ForMember(dest =&gt; dest.ShirtColor, // dest =&gt; dest.MapFrom( // src =&gt; src.ShirtColor != null // ? new OptionSetValue((int) src.ShirtColor) // : null)); PersonA source = new PersonA(); source.FirstName = "Thomas"; source.LastName = "Jefferson"; source.ShirtColor = null; // nullable int PersonB destination = new PersonB(); destination.FirstName = "Thomas"; destination.LastName = "Jefferson"; destination.ShirtColor = new OptionSetValue(4); // Results in: "Nullable object must have a value" despite the fact that // condition should have been met! Mapper.Map&lt;PersonA, PersonB&gt;(source, destination); Debug.Assert(destination.ShirtColor != null); Console.WriteLine("Our existing data was not overwritten!!"); Console.WriteLine("Hit enter to exit"); Console.ReadLine(); </code></pre> <p>Here is how OptionSet is defined: public class OptionSetValue { public OptionSetValue(){}</p> <pre class="lang-cs prettyprint-override"><code> public OptionSetValue(int value) { Number = value; } public int Number { get; set; } } </code></pre>
 

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