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?


当前回答

您正在使用MapToStoredProcedures(),这表明您正在将实体映射到存储过程,在执行此操作时,您需要放弃存在存储过程的事实,并正常使用上下文。 像这样(写入浏览器,所以没有测试)

using(MyContext context = new MyContext())
{
    Department department = new Department()
    {
        Name = txtDepartment.text.trim()
    };
    context.Set<Department>().Add(department);
}

如果你真正想做的只是直接调用存储过程,那么使用SqlQuery

其他回答

现在还可以使用我创建的约定,该约定允许从EF本机调用存储过程(包括返回多个结果集的存储过程)、tvf和标量udf。

在实体框架6.1发布之前,存储函数(即表值函数和存储过程)只能在数据库优先的情况下在EF中使用。有一些变通办法可以在Code First应用中调用存储函数,但你仍然不能在Linq查询中使用tvf,这是最大的限制之一。在EF 6.1中,映射API是公开的(以及一些额外的调整),这使得在Code First应用中使用存储函数成为可能。

阅读更多

在过去的两周里,我一直在努力推广,现在终于有了这个约定的beta版本,它允许在使用代码优先方法和实体框架6.1.1(或更新版本)的应用程序中使用存储函数(即存储过程、表值函数等)。我对这个版本中包含的修复和新功能非常满意。

阅读更多。

object[] xparams = {
            new SqlParameter("@ParameterWithNumvalue", DBNull.Value),
            new SqlParameter("@In_Parameter", "Value"),
            new SqlParameter("@Out_Parameter", SqlDbType.Int) {Direction = ParameterDirection.Output}};

YourDbContext.Database.ExecuteSqlCommand("exec StoredProcedure_Name @ParameterWithNumvalue, @In_Parameter, @Out_Parameter", xparams);
var ReturnValue = ((SqlParameter)params[2]).Value;  
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();
        }

这是EF (DB first)在DbContext类中生成的:

public ObjectResult<int> Insert_Department(string department)
{
    var departmentParameter = new ObjectParameter("department", department);

    return ((IObjectContextAdapter)this).ObjectContext.ExecuteFunction<int>("insert_department", departmentParameter);
}

.NET Core 5.0没有FromSql,而是有frommsqlraw

下面这些都对我有用。这里的帐户类是c#中的实体,具有与数据库中完全相同的表和列名。

App配置类如下所示

class AppConfiguration
{
    public AppConfiguration()
    {
        var configBuilder = new ConfigurationBuilder();
        var path = Path.Combine(Directory.GetCurrentDirectory(), "appsettings.json");
        configBuilder.AddJsonFile(path, false);
        var root = configBuilder.Build();
        var appSetting = root.GetSection("ConnectionStrings:DefaultConnection");
        sqlConnectionString = appSetting.Value;
    }

    public string sqlConnectionString { get; set; }
}

DbContext类:

public class DatabaseContext : DbContext
{
    public class OptionsBuild
    {
        public OptionsBuild()
        {
            setting = new AppConfiguration();
            opsBuilder = new DbContextOptionsBuilder<DatabaseContext>();
            opsBuilder.UseSqlServer(setting.sqlConnectionString);
            dbOptions = opsBuilder.Options;
        }

        public DbContextOptionsBuilder<DatabaseContext> opsBuilder { get; set; }
        public DbContextOptions<DatabaseContext> dbOptions { get; set; }

        private AppConfiguration setting { get; set; }
    }

    public static OptionsBuild ops = new OptionsBuild();

    public DatabaseContext(DbContextOptions<DatabaseContext> options) : base(options)
    {
        //disable initializer
        //  Database.SetInitializer<DatabaseContext>(null);
    }

    public DbSet<Account> Account { get; set; }
}

这段代码应该在你的数据访问层:

List<Account> accounts = new List<Account>();
var context = new DatabaseContext(DatabaseContext.ops.dbOptions);
accounts = await context.Account.ToListAsync();   //direct select from a table

var param = new SqlParameter("@FirstName", "Bill");
accounts = await context.Account.FromSqlRaw<Account>("exec Proc_Account_Select", 
param).ToListAsync();            //procedure call with parameter
        
accounts = context.Account.FromSqlRaw("SELECT * FROM dbo.Account").ToList();  //raw query