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POLinq Expression - Invalid Arguments
 

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  1. POLinq Expression - Invalid Arguments
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    <pre><code>public class EcImageWrapper { //etc... public IQueryable&lt;EcFieldWrapper&gt; ListOfFields { get { //logic here return this.listOfFields.AsQueryable(); } } public EcFieldWrapper FindBy(Expression&lt;Func&lt;EcFieldWrapper, int, bool&gt;&gt; predicate) { return this.ListOfFields.Where(predicate).SingleOrDefault(); } public EcFieldWrapper FindByName(string fieldName) { return this.FindBy(x =&gt; x.Name.ToUpper() == fieldName.ToUpper()); //error here, wanting 3 arguments //which makes sense as the above Expression has 3 //but i don't know how to get around this } </code></pre> <p>For some reason the Expression> Is requiring me to use 3 arguments, in the past I've only used 2 for the instance in question. However, now I'm wanting to do a find by on a collection within this instance.</p> <p>I'm getting the following errors:</p> <pre><code>Delegate 'System.Func&lt;MSDORCaptureUE.Wrappers.EcFieldWrapper,int,bool&gt;' does not take 1 arguments The best overloaded method match for 'CaptureUE.Wrappers.EcImageWrapper.FindBy(System.Linq.Expressions.Expression&lt;System.Func&lt;CaptureUE.Wrappers.EcFieldWrapper,int,bool&gt;&gt;)' has some invalid arguments Argument 1: cannot convert from 'string' to 'System.Linq.Expressions.Expression&lt;System.Func&lt;CaptureUE.Wrappers.EcFieldWrapper,int,bool&gt;&gt;' </code></pre> <p>Desired outcome: To be able to use a predicate of the return type EcFieldWrapper and predicate type of EcFieldWrapper within the instance of a class EcImageWrapper</p> <p>Why does it require 3? Why the int?</p>
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    1. USbizah
    1. USbizah
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      1. VTUpMod
    1. COWhat *exactly* do you mean by "the expression is requiring me to use three arguments"? What happens if you change your method to just an `Expression<Func<EcFieldWrapper, bool>>`?
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      1. USJon Skeet
    2. COHrm... I could have sworn this threw an error when i did this earlier. It seems to not be throwing an error now when i try it.
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      1. USbizah
 

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