SQL 服务器包含谓词不适用于多个搜索词

Question

我有一个 c# 程序可以根据用户的输入搜索 table。

关键词被space分割后存入数组

然后 switch 语句将 select 基于仅输入一个词或两个词的正确大小写。

我的 switch 语句只为第一种情况填充我的数据网格，但是当尝试使用第二种情况时，我的程序会捕获异常。

我试过调试，但我唯一看到的是当我进入案例2时，它没有超出sda1.Fill(dt1);

更新代码：

static string myconnstr = ConfigurationManager.ConnectionStrings["connstrng"].ConnectionString;       

private void btnSearch_Click(object sender, EventArgs e)
{
    //Get the value from textbox
    string keyword = txtboxKeyword.Text;
    string[] words = keyword.Split(' ');

    //SQL Connection
    var conn = new SqlConnection(myconnstr);

    try
    {
        switch (words.Length)
        {
            case 1:
                    //Declare Command object with parameter
                    SqlCommand cmd = new SqlCommand("SELECT Site, StreetAddress, City, State, Zip, PharmacyPhone, MDVersion, InstallDate, SiteCodes, SiteNotActive, CloseDate, SiteNotes " +
                                    "FROM Sites WHERE contains(site, @words0) OR contains (StreetAddress, @words0) OR contains(city, @words0)", conn);

                    cmd.Parameters.AddWithValue("@words0", words[0]);

                    SqlDataAdapter sda = new SqlDataAdapter(cmd);
                    DataTable dt = new DataTable();
                    sda.Fill(dt);
                    dataGridSites.ReadOnly = true;
                    dataGridSites.DataSource = dt;
                    dataGridSites.CurrentCell = null;
                    break;
                case 2:
                    //Declare Command object with parameter
                    SqlCommand cmd1 = new SqlCommand("SELECT Site, StreetAddress, City, State, Zip, PharmacyPhone, MDVersion, InstallDate, SiteCodes, SiteNotActive, CloseDate, SiteNotes " +
                                    "FROM Sites WHERE contains(site, @words0, @words1) OR contains (StreetAddress, @words0, @words1) OR contains(city, @words0, @words1)", conn);

                    cmd1.Parameters.AddWithValue("@words0", words[0]);
                    cmd1.Parameters.AddWithValue("@words1", words[1]);

                    SqlDataAdapter sda1 = new SqlDataAdapter(cmd1);
                    DataTable dt1 = new DataTable();
                    sda1.Fill(dt1);
                    dataGridSites.ReadOnly = true;
                    dataGridSites.DataSource = dt1;
                    dataGridSites.CurrentCell = null;
                    break;                   
        }
    }
    catch (Exception)
    {
        MessageBox.Show("Search cannot be blank.");
    }            
}

这是我收到的更新后的异常错误：

System.Data.SqlClient.SqlException (0x80131904): Incorrect syntax near '@words1'. Error Number:102,State:1,Class:15

Answer 1

我认为这是 switch case 已知的作用域问题，因为历史上 reasons.That 为什么我们必须在每个语句之后放置 break。试试看这里。 Variable declaration in a C# switch statement

Answer 2

您现有代码不起作用的原因是 contains 不支持您当前尝试调用它的方式中的三个参数。

根据 documentation，我建议更改：

FROM Sites WHERE contains(site, @words0) OR contains (StreetAddress, @words0) OR contains(city, @words0)

至：

FROM Sites WHERE contains((site, StreetAddress, city), @words0)

并且：

FROM Sites WHERE contains(site, @words0, @words1) OR contains (StreetAddress, @words0, @words1) OR contains(city, @words0, @words1)

至：

FROM Sites WHERE contains((site, StreetAddress, city), @words0) OR contains((site, StreetAddress, city), @words1)

如果您真的想使用当前更详细的样式，那么 Example I 建议：

FROM Sites WHERE contains(site, @wordsConcat) OR contains (StreetAddress, @wordsConcat) OR contains(city, @wordsConcat)

可能工作，其中 @wordsConcat 已设置（由 C#）为：

words[0] + " OR " + words[1]

SQL 服务器包含谓词不适用于多个搜索词

SQL Server contains predicate not working with multiple search terms

c#

sql-server

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