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我有一个带有编译查询的静态类，我想重用一些子查询。所以我将一个公共部分提取到一个静态属性中，然后在多个查询中引用它：

public static class Query {
    // common part
    static Func<MyDataContext, string, IQueryable<UserAccount>> accounts = 
        (db, cID) => db.UserAccount
                .Where(x => x.XRef.cID == cID && bla-bla-bla);

    // one of queries that reuse 'accounts' part
    public static readonly Func<MyDataContext, string, string, bool> CheckClientIdentity =
        CompiledQuery.Compile<MyDataContext, string, string, bool>(
            (db, cID, identityName) => accounts(db, cID)
                .Any(x => x.IdentityName == identityName)
        );
}

这编译得很好，但在运行时我得到

System.InvalidOperationException：“UserAccount”的成员访问“System.String IdentityName”在“System.Linq.IQueryable`1[UserAccount] 类型上不合法。

在这种情况下也不例外

public static readonly Func<MyDataContext, string, string, bool> CheckClientIdentity =
    CompiledQuery.Compile<MyDataContext, string, string, bool>(
        (db, cID, identityName) => db.UserAccount
            .Where(x => x.XRef.cID == cID && bla-bla-bla)
            .Any(x => x.IdentityName == identityName)
    );

为什么？任何解决方法？

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0 回答 0