使用linq按相关性对结果进行排序

时间:2013-10-11 12:40:39

标签: asp.net-mvc linq

我正在Intranet网站上运行一个简单的搜索,我想根据查询的相关性对结果进行排序。

这是我到目前为止所拥有的。

var customer = from c in db.Customer
               select c;

if (!String.IsNullOrEmpty(searchString))
{
    customer = customer.Where(c => SqlFunctions.StringConvert((double)c.CustomerID).Trim().Equals(searchString)
    || c.CustomerName.ToUpper().Contains(searchString.ToUpper())
    || SqlFunctions.SoundCode(c.CustomerName.ToUpper()) == SqlFunctions.SoundCode(searchString.ToUpper()));
}

switch (s)
{
    case "NameDesc":
        customer = customer.OrderByDescending(c => c.CustomerName);
        break;
    default:
        customer = customer.OrderBy(c => c.CustomerName);
        break;
}

因为我正在使用声音它正在返回其他可能的匹配,这对我很有用,但是我希望与搜索框中输入的内容最接近的匹配首先显示在结果中。

这可以在OrderBy上使用查询吗?还是我需要使用FullText搜索?

1 个答案:

答案 0 :(得分:0)

尝试在查询中添加权重参数:

customersLevel1 = customer
.Where(c => SqlFunctions.StringConvert((double)c.CustomerID).Trim().Equals(searchString))
.Select(c => new { cust = c, weight = 1});

customersLevel2 = customer
.Where(c => c.CustomerName.ToUpper().Contains(searchString.ToUpper()))
.Select(c => new { cust = c, weight = 2});

customersLevel3 = customer
.Where(c => SqlFunctions.SoundCode(c.CustomerName.ToUpper()) == SqlFunctions.SoundCode(searchString.ToUpper()))
.Select(c => new { cust = c, weight = 3});

然后,要通过一个查询检索数据到DB,您可以使用Union():

var result = (customersLevel1)
             .Union(customersLevel2)
             .Union(customersLevel3)
             .OrderBy(c => c.weight)
             .Select(c => c.cust);