非泛型声明中不允许约束

Arp*_*hah 4 .net generics methods

 private Result Execute(
     out T returnValue, 
     string storedProcedureName, 
     Hashtable parameters, 
     ExecuteType executeType) 
   where T : class
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以下错误意味着什么,我该如何解决?

错误在何处:非泛型声明中不允许约束

dle*_*lev 19

private Result Execute<T>(
                           out T returnValue, 
                           string storedProcedureName, 
                           Hashtable parameters, 
                           ExecuteType executeType
                         ) where T : class
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注意<T>后面的要求Execute.