Question

我有两个IQueryables：

    public static IQueryable<Counterparty> SearchByCode(this IQueryable<Counterparty> queryable, string searchQuery)
    {
        return queryable.Where(x => x.Code.StartsWith(searchQuery.ToUpper()));
    }

    public static IQueryable<Counterparty> SearchByName(this IQueryable<Counterparty> queryable, string searchQuery)
    {
        return queryable.Where(x => x.Name.ToLower().Contains(searchQuery.ToLower()));
    }

我想创建另一个IQueryable，它将两个查询组合为OR，例如

    public static IQueryable<Counterparty> SearchByCodeOrName(this IQueryable<Counterparty> queryable, string searchQuery)
    {
        // return SearchByName(searchQuery) OR SearchByCode(searchQuery)
    }

我宁愿避免重复代码，所以我想重用现有的可查询而不是重写一个新的lambda表达式，如Where(x=> x.Code.StartsWith.... || x.Name.Contains.....)

Answer 1

你可能会。两者结合在一起

public static IQueryable<Counterparty> SearchByCodeOrName(this IQueryable<Counterparty> queryable, string searchQuery)
{
     return SearchByName(searchQuery).Union(SearchByCode(searchQuery))
}

Answer 2

根据您希望能够重用的代码，这可能是您不重复查询条件内部工作的替代方法：

    private static Func<Counterparty, string, bool> CodeStartsWith = (x, searchQuery) => x.Code.StartsWith(searchQuery.ToUpper());

    private static Func<Counterparty, string, bool> NameContains = (x, searchQuery) => x.Name.Contains(searchQuery.ToLower());

    public static IQueryable<Counterparty> SearchByCode(this IQueryable<Counterparty> queryable, string searchQuery)
    { 
        return queryable.Where(x => CodeStartsWith(x, searchQuery)); 
    }

    public static IQueryable<Counterparty> SearchByName(this IQueryable<Counterparty> queryable, string searchQuery)
    {
        return queryable.Where(x => NameContains(x, searchQuery)); 
    }

    public static IQueryable<Counterparty> SearchByCodeOrName(this IQueryable<Counterparty> queryable, string searchQuery)
    {
        return queryable.Where(x => NameContains(x, searchQuery) || CodeStartsWith(x, searchQuery)); 
    }

执行两个LINQ IQueryable的OR

2 个答案: