C#-如何简化是否使用实体框架

如何简化以下代码：

public List<Cwzz_CashFlowItem> AllDataPage(int start, int limit, out int total, string xmbmLike, string xmmcLike)
{
    List<Cwzz_CashFlowItem> ll;
    if (xmbmLike != "" && xmmcLike != "")
    {
        total = _ctx.Cwzz_CashFlowItem
                    .Where(v => v.CashFlowCode.Contains(xmbmLike))
                    .Count(v => v.CashFlowName.Contains(xmmcLike));

        ll = _ctx.Cwzz_CashFlowItem
                 .Where(v => v.CashFlowCode.Contains(xmbmLike))
                 .Where(v => v.CashFlowName.Contains(xmmcLike))
                 .OrderBy(v => v.CashFlowCode).Skip(start).Take(limit).ToList();
    }
    else if (xmbmLike != "" && xmmcLike == "")
    {
        total = _ctx.Cwzz_CashFlowItem
                    .Count(v => v.CashFlowCode.Contains(xmbmLike));

        ll = _ctx.Cwzz_CashFlowItem
                 .Where(v => v.CashFlowCode.Contains(xmbmLike))
                 .OrderBy(v => v.CashFlowCode).Skip(start).Take(limit).ToList();
    }
    else if (xmbmLike == "" && xmmcLike != "")
    {
        total = _ctx.Cwzz_CashFlowItem
                    .Count(v => v.CashFlowName.Contains(xmmcLike));

        ll = _ctx.Cwzz_CashFlowItem
                 .Where(v => v.CashFlowName.Contains(xmmcLike))
                 .OrderBy(v => v.CashFlowCode).Skip(start).Take(limit).ToList();
    }
    else
    {
        total = _ctx.Cwzz_CashFlowItem.Count();

        ll = _ctx.Cwzz_CashFlowItem
                 .OrderBy(v => v.CashFlowCode)
                 .Skip(start).Take(limit).ToList();
    }
    return ll;
}

如果存在更多条件而不是两个条件,则if-else会更加复杂,因此如何简化上面的代码.

解决方法:

Linq表达式可以被链接.避免过早强制转换为List.

 public IQueryable<Cwzz_CashFlowItem> AllDataPage(...) {
    IQueryable<Cwzz_CashFlowItem> ll =  _ctx.Cwzz_CashFlowItem;

    if (xmbmLike != "")
    {
      ll = ll.Where(v => v.CashFlowCode.Contains(xmbmLike));
    }

    if (xmcmLike != "")
    {
      ll = ll.Where(v => v.CashFlowCode.Contains(xmcmLike));
    }

    return ll.OrderBy(v => v.CashFlowCode).Skip(start).Take(limit);
   }

我将把退货算作练习.

标签：if-statement,sql,c,entity-framework
来源： https://codeday.me/bug/20191122/2060628.html