Linq中两种更新操作

方法一：Attach方法

EmployeeDAL
/// <summary>

/// 更新雇员信息

/// </summary>

/// <param name="e"></param>

public void UpdateEmploee(Employee e)

{

try

{

dc.Employee.Attach(e);

dc.Refresh(RefreshMode.KeepCurrentValues, e);

dc.SubmitChanges(ConflictMode.ContinueOnConflict);

}

catch(Exception ex)

{

throw ex;

}

}

ThreeTierBLL

/// <summary>

/// 更新雇员信息

/// </summary>

/// <param name="e"></param>

public static void UpdateEmploee(Employee e)

{

new EmployeeDAL().UpdateEmploee(e);

}

Web

protected void btnSubmit_Click(object sender, EventArgs e)

{

Employee emp = new Employee();

emp.EmployeeID = this.txtEmpID.Text;

emp.EmployeeName = this.txtEmpName.Text;

emp.EmployeePhone = this.txtEmpPhone.Text;

emp.DepartmentID = Convert.ToInt32(this.txtDepID.Text);

EmployeeBLL.UpdateEmploee(emp);

}

方法二：读出现有字段，更改
DAL
/// <summary>

/// 根据工号修改手机号

/// </summary>

/// <param name="num">工号</param>

/// <param name="newphone">新的手机号</param>

public void ModifyCellPhoneByNum(string num, string newphone)

{

try

{

var stu = (from s in dc.TeacherBasicInformation

where s.TeacherNum == num

select s).FirstOrDefault();

stu.TeacherCellPhone = newphone;

dc.SubmitChanges();

}

catch

{ }

}

BLL

/// <summary>

/// 根据工号修改手机号

/// </summary>

/// <param name="num">工号</param>

/// <param name="newphone">新的手机号</param>

public static void ModifyCellPhoneByNum(string num, string newphone)

{

new TeacherDAL().ModifyCellPhoneByNum(num, newphone);

}

web

/// <summary>

/// 编辑中的更新

/// </summary>

protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)

{

if (((TextBox)GridView1.Rows[e.RowIndex].Cells[2].Controls[0]).Text.Trim() == "")

{

PageExtension.Alert(this, "新的手机号不能为空！");

}

else

{

TeacherBLL.ModifyCellPhoneByNum(GridView1.DataKeys[e.RowIndex].Value.ToString(),

((TextBox)GridView1.Rows[e.RowIndex].Cells[2].Controls[0]).Text.Trim());

this.GridView1.EditIndex = -1;

Bind();

}

}