c# - 插入带有 where 子句的语句 c#

Question

我正在尝试根据 cookie 的值将详细信息插入表中，.这是代码

   SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["RegistrationConnectionString"].ConnectionString);
        conn.Open();
        string insertQuery = "insert into Details (Employees, Performance, TotalPerformance, Attitude, TotalAttitude) values(@employees, @performance ,@totalPerformance, attitude, totalAttitude)";
        SqlCommand com = new SqlCommand(insertQuery, conn);
        com.Parameters.AddWithValue("@employees", Request.QueryString["employees"]);
        com.Parameters.AddWithValue("@performance", totalPer.ToString());
        com.Parameters.AddWithValue("@totalPerformance", totalPercent.ToString());
        com.Parameters.AddWithValue("@attitude", totalAtt.ToString());
        com.Parameters.AddWithValue("@totalattitude", totalPercent.ToString());



        com.ExecuteNonQuery();

这很好用，但在字符串插入查询行中，我想添加一个 where 子句，如果该行中“name”列的值与 cookie 匹配，它将把值插入到特定行中。我不知道正确的语法 感谢您的帮助

Answer 1

你需要一个 UPDATE语句，而不是 INSERT 语句，因为您要修改现有记录。

using (
    SqlConnection conn =
        new SqlConnection(
            ConfigurationManager.ConnectionStrings["RegistrationConnectionString"].ConnectionString))
{
    conn.Open();
    string updateQuery =
        @"UPDATE Details 
        SET Employees = @employeee, 
        Performance = @performance , 
        TotalPerformance = @totalPerformance,
        Attitude = @attitude,
        TotalAttitude = @totalattitude
        WHERE yourField = @yourConditionValue";

    using (SqlCommand com = new SqlCommand(updateQuery, conn))
    {
        com.Parameters.AddWithValue("@employees", Request.QueryString["employees"]);
        com.Parameters.AddWithValue("@performance", totalPer.ToString());
        com.Parameters.AddWithValue("@totalPerformance", totalPercent.ToString());
        com.Parameters.AddWithValue("@attitude", totalAtt.ToString());
        com.Parameters.AddWithValue("@totalattitude", totalPercent.ToString());
        com.Parameters.AddWithValue("@yourConditionValue", yourValue);
        com.ExecuteNonQuery();
    }
}

+1，用于在您的问题中使用参数，另一件事，enclose your Command and Connection object in using 语句。