我对实体框架6非常陌生,我想在我的项目中实现存储过程。我有一个存储过程如下:
ALTER PROCEDURE [dbo].[insert_department]
@Name [varchar](100)
AS
BEGIN
INSERT [dbo].[Departments]([Name])
VALUES (@Name)
DECLARE @DeptId int
SELECT @DeptId = [DeptId]
FROM [dbo].[Departments]
WHERE @@ROWCOUNT > 0 AND [DeptId] = SCOPE_IDENTITY()
SELECT t0.[DeptId]
FROM [dbo].[Departments] AS t0
WHERE @@ROWCOUNT > 0 AND t0.[DeptId] = @DeptId
END
系类:
public class Department
{
public int DepartmentId { get; set; }
public string Name { get; set; }
}
modelBuilder
.Entity<Department>()
.MapToStoredProcedures(s =>
s.Update(u => u.HasName("modify_department")
.Parameter(b => b.Department, "department_id")
.Parameter(b => b.Name, "department_name"))
.Delete(d => d.HasName("delete_department")
.Parameter(b => b.DepartmentId, "department_id"))
.Insert(i => i.HasName("insert_department")
.Parameter(b => b.Name, "department_name")));
protected void btnSave_Click(object sender, EventArgs e)
{
string department = txtDepartment.text.trim();
// here I want to call the stored procedure to insert values
}
我的问题是:如何调用存储过程并将参数传递给它?
public static string ToSqlParamsString(this IDictionary<string, string> dict)
{
string result = string.Empty;
foreach (var kvp in dict)
{
result += $"@{kvp.Key}='{kvp.Value}',";
}
return result.Trim(',', ' ');
}
public static List<T> RunSproc<T>(string sprocName, IDictionary<string, string> parameters)
{
string command = $"exec {sprocName} {parameters.ToSqlParamsString()}";
return Context.Database.SqlQuery<T>(command).ToList();
}
用你的例子,这里有两种方法来实现这一点:
方法#1:使用存储过程映射
请注意,这段代码可以使用映射,也可以不使用映射。如果在实体上关闭映射,EF将生成一个插入+选择语句。
protected void btnSave_Click(object sender, EventArgs e)
{
using (var db = DepartmentContext() )
{
var department = new Department();
department.Name = txtDepartment.text.trim();
db.Departments.add(department);
db.SaveChanges();
// EF will populate department.DepartmentId
int departmentID = department.DepartmentId;
}
}
方法#2:直接调用存储过程
protected void btnSave_Click(object sender, EventArgs e)
{
using (var db = DepartmentContext() )
{
var name = new SqlParameter("@name", txtDepartment.text.trim());
//to get this to work, you will need to change your select inside dbo.insert_department to include name in the resultset
var department = db.Database.SqlQuery<Department>("dbo.insert_department @name", name).SingleOrDefault();
//alternately, you can invoke SqlQuery on the DbSet itself:
//var department = db.Departments.SqlQuery("dbo.insert_department @name", name).SingleOrDefault();
int departmentID = department.DepartmentId;
}
}
我建议使用第一种方法,因为您可以直接使用department对象,而不必创建一堆SqlParameter对象。
我发现以代码优先的方式调用存储过程并不方便。
我更喜欢用Dapper代替。
下面的代码是用实体框架编写的:
var clientIdParameter = new SqlParameter("@ClientId", 4);
var result = context.Database
.SqlQuery<ResultForCampaign>("GetResultsForCampaign @ClientId", clientIdParameter)
.ToList();
以下代码是用Dapper编写的:
return Database.Connection.Query<ResultForCampaign>(
"GetResultsForCampaign ",
new
{
ClientId = 4
},
commandType: CommandType.StoredProcedure);
我认为第二段代码更容易理解。