c# - Expression.Body as MemberExpression returns null for primitive property -

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i using code set value of property via reflection :

public static void set<t>(this t target, expression<func<t, object>> memberlamda, object value) {     var memberselectorexpression = memberlamda.body memberexpression;     if (memberselectorexpression != null)     {         var property = memberselectorexpression.member propertyinfo;         if (property != null)         {             property.setvalue(target, value, null);         }     } }

but reason when : 

myobject.set(x=>x.id, 1);

where id of type int, can see memberselectorexpression null. have no issue properties of reference type.

i not familiar yet expression trees, doing wrong ?

the solution use following signature :

public static void set<t, tprop>(this t target, expression<func<t, tprop>> memberlamda,    tprop value)

to make sure memberexpression correctly inferred. "object" generic constraint not specific enough.


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