问题
I have an extension method to get property name as
public static string Name<T>(this Expression<Func<T>> expression)
{
MemberExpression body = (MemberExpression)expression.Body;
return body.Member.Name;
}
I am calling it as
string Name = ((Expression<Func<DateTime>>)(() => this.PublishDateTime)).Name();
This is working fine and returns me PublishDateTime
as string.
However I have an issue with the calling statement, it is looking too complex and I want some thing like this.
this.PublishDateTime.Name()
Can some one modify my extension method?
回答1:
Try this:
public static string Name<T,TProp>(this T o, Expression<Func<T,TProp>> propertySelector)
{
MemberExpression body = (MemberExpression)propertySelector.Body;
return body.Member.Name;
}
The usage is:
this.Name(x=>x.PublishDateTime);
回答2:
With C# 6.0, you can use:
nameof(PublishDateTime)
回答3:
You can't do this.PublishDateTime.Name()
, as the only thing that will be passed into the extension method is the value or reference on which you call the extension method.
Whether it's a property, field, local variable or method result doesn't matter, it won't have a name that you can access inside the extension method.
The expression will be "verbose", see How can I add this method as an extension method to properties of my class? (thanks @Black0ut) to put it in a static helper class.
来源:https://stackoverflow.com/questions/32376472/extension-method-to-get-property-name