将存储过程中的“选择查询”的结果返回到列表
本文关键字:结果 返回 列表 选择查询 选择 存储过程 存储 过程中 查询 | 更新日期: 2023-09-27 18:31:57
我正在编写一个当前仅包含SELECT
查询的存储过程。它将被扩展以执行许多其他操作,这就是为什么它必须是存储过程的原因,但现在,它是一个简单的查询。
像这样:
SELECT name, occupation, position
FROM jobs
WHERE ...
我希望返回要在 C# 中使用的此查询的结果。我想将其添加到列表中,以便可以将其绑定到 GridView 组件。
不过,我不知道该怎么做。如果我必须在返回所有选定数据后将其插入到列表中,那没关系,我只需要知道如何正确返回数据,以便我可以做到这一点。
但是,如果我能以可以直接弹出到列表中的格式返回它,那将是理想的。
在存储过程中,您只需要编写如下所示的选择查询:
CREATE PROCEDURE TestProcedure
AS
BEGIN
SELECT ID, Name
FROM Test
END
在 C# 端,可以使用读取器、数据表、适配器进行访问。
使用适配器刚刚由Susanna Floora解释。
使用阅读器:
SqlConnection connection = new SqlConnection(ConnectionString);
command = new SqlCommand("TestProcedure", connection);
command.CommandType = System.Data.CommandType.StoredProcedure;
connection.Open();
SqlDataReader reader = command.ExecuteReader();
List<Test> TestList = new List<Test>();
Test test = null;
while (reader.Read())
{
test = new Test();
test.ID = int.Parse(reader["ID"].ToString());
test.Name = reader["Name"].ToString();
TestList.Add(test);
}
gvGrid.DataSource = TestList;
gvGrid.DataBind();
使用数据表:
SqlConnection connection = new SqlConnection(ConnectionString);
command = new SqlCommand("TestProcedure", connection);
command.CommandType = System.Data.CommandType.StoredProcedure;
connection.Open();
DataTable dt = new DataTable();
dt.Load(command.ExecuteReader());
gvGrid.DataSource = dt;
gvGrid.DataBind();
我希望它能帮助你。 :)
SqlConnection connection = new SqlConnection(ConnectionString);
command = new SqlCommand("TestProcedure", connection);
command.CommandType = System.Data.CommandType.StoredProcedure;
connection.Open();
DataTable dt = new DataTable();
dt.Load(command.ExecuteReader());
gvGrid.DataSource = dt;
gvGrid.DataBind();
SqlConnection con = new SqlConnection("Data Source=DShp;Initial Catalog=abc;Integrated Security=True");
SqlDataAdapter da = new SqlDataAdapter("data", con);
da.SelectCommand.CommandType= CommandType.StoredProcedure;
DataSet ds=new DataSet();
da.Fill(ds, "data");
GridView1.DataSource = ds.Tables["data"];
GridView1.DataBind();
在存储过程中传递参数并在 C# 代码中调用它,如下所示?
SqlConnection conn = new SqlConnection(func.internalConnection);
var cmd = new SqlCommand("usp_CustomerPortalOrderDetails", conn);
cmd.CommandType = System.Data.CommandType.StoredProcedure;
cmd.Parameters.Add("@CustomerId", SqlDbType.Int).Value = customerId;
cmd.Parameters.Add("@Qid", SqlDbType.VarChar).Value = qid;
conn.Open();
// Populate Production Panels
DataTable listCustomerJobDetails = new DataTable();
listCustomerJobDetails.Load(cmd.ExecuteReader());
conn.Close();
我有同样的问题,花了很长时间才找到一个简单的解决方案。
使用 ASP.NET MVC 5 和 EF 6
:将存储过程添加到.edmx
模型时,存储过程的结果将通过自动生成的名为 yourStoredProcName_result
的对象传递。
此_result
对象包含与存储过程选择的数据库中的列对应的属性。
_result
类可以简单地转换为列表:
yourStoredProcName_result.ToList()
// GET: api/GetStudent
public Response Get() {
return StoredProcedure.GetStudent();
}
public static Response GetStudent() {
using (var db = new dal()) {
var student = db.Database.SqlQuery<GetStudentVm>("GetStudent").ToList();
return new Response {
Sucess = true,
Message = student.Count() + " Student found",
Data = student
};
}
}
基于这里的一些回应,我想添加另一种方式。使用反射创建一个泛型方法,该方法可以将任何存储过程响应映射到列表。也就是说,只要给定类型包含与响应中的存储过程列名称类似的成员,就可以使用所需的任何类型的 List。理想情况下,我可能会使用 Dapper - 但这里是:
private static SqlConnection getConnectionString() // Should be gotten from config in secure storage.
{
SqlConnectionStringBuilder builder = new SqlConnectionStringBuilder();
builder.DataSource = "it.hurts.when.IP";
builder.UserID = "someDBUser";
builder.Password = "someDBPassword";
builder.InitialCatalog = "someDB";
return new SqlConnection(builder.ConnectionString);
}
public static List<T> ExecuteSP<T>(string SPName, List<SqlParameter> Params)
{
try
{
DataTable dataTable = new DataTable();
using (SqlConnection Connection = getConnectionString())
{
// Open connection
Connection.Open();
// Create command from params / SP
SqlCommand cmd = new SqlCommand(SPName, Connection);
// Add parameters
cmd.Parameters.AddRange(Params.ToArray());
cmd.CommandType = CommandType.StoredProcedure;
// Make datatable for conversion
SqlDataAdapter da = new SqlDataAdapter(cmd);
da.Fill(dataTable);
da.Dispose();
// Close connection
Connection.Close();
}
// Convert to list of T
var retVal = ConvertToList<T>(dataTable);
return retVal;
}
catch (SqlException e)
{
Console.WriteLine("ConvertToList Exception: " + e.ToString());
return new List<T>();
}
}
/// <summary>
/// Converts datatable to List<someType> if possible.
/// </summary>
public static List<T> ConvertToList<T>(DataTable dt)
{
try // Necesarry unfotunately.
{
var columnNames = dt.Columns.Cast<DataColumn>()
.Select(c => c.ColumnName)
.ToList();
var properties = typeof(T).GetProperties();
return dt.AsEnumerable().Select(row =>
{
var objT = Activator.CreateInstance<T>();
foreach (var pro in properties)
{
if (columnNames.Contains(pro.Name))
{
if (row[pro.Name].GetType() == typeof(System.DBNull)) pro.SetValue(objT, null, null);
else pro.SetValue(objT, row[pro.Name], null);
}
}
return objT;
}).ToList();
}
catch (Exception e)
{
Console.WriteLine("Failed to write data to list. Often this occurs due to type errors (DBNull, nullables), changes in SP's used or wrongly formatted SP output.");
Console.WriteLine("ConvertToList Exception: " + e.ToString());
return new List<T>();
}
}
要点:https://gist.github.com/Big-al/4c1ff3ed87b88570f8f6b62ee2216f9f
也许这会有所帮助:
从数据库获取行:
public static DataRowCollection getAllUsers(string tableName)
{
DataSet set = new DataSet();
SqlCommand comm = new SqlCommand();
comm.Connection = DAL.DAL.conn;
comm.CommandType = CommandType.StoredProcedure;
comm.CommandText = "getAllUsers";
SqlDataAdapter da = new SqlDataAdapter();
da.SelectCommand = comm;
da.Fill(set,tableName);
DataRowCollection usersCollection = set.Tables[tableName].Rows;
return usersCollection;
}
从 DataRowCollection 填充 DataGridView:
public static void ShowAllUsers(DataGridView grdView,string table, params string[] fields)
{
DataRowCollection userSet = getAllUsers(table);
foreach (DataRow user in userSet)
{
grdView.Rows.Add(user[fields[0]],
user[fields[1]],
user[fields[2]],
user[fields[3]]);
}
}
实现:
BLL.BLL.ShowAllUsers(grdUsers,"eusers","eid","euname","eupassword","eposition");