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var s = db.Account.Select(c => c.ID);
var ret =(from t in db.Profile
 where s.Contains(t.ID)
 select t).ToList();
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var ids=db.Account.Select(c => c.ID);
var ret = (from t in db.Profile where ids.Any(c=>c==t.UserID) select t).ToList();
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int[] ids = new int[]{10101,10005,10007};
var ret = (from t in db.Profile where ids.Any(c=>c==t.UserID) select t).ToList();
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Ìæ´ú·½·¨2:¹¹ÔìLambdaÓï¾ä
        private static Expression<Func<TElement, bool>> BuildWhereInExpression<TElement, TValue>(Expression<Func<TElement, TValue>> propertySelector, IEnumerable<TValue> values)
        {
            ParameterExpression p = propertySelector.Parameters.Single();
            if (!values.Any())
                return e => false;
            var equals = values.Select(value => (Expression)Expression.Equal(propertySelector.Body, Expression.Constant(value, typeof(TValue))));
            var body&


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