EntitySet调用add方法去没有改变Untracked state
本帖最后由 XieeEvil 于 2012-04-08 17:00:39 编辑 EntitySet 调用add方法后没有将object state 从Untracked 修改为可被datacontext跟踪的状态，导致
EntitySet add一个新的Entity或修改里面的一个实体 调用submitchanges后发现数据库没有保存更改
下面试代码：
初始化：
IEnumerable<T_XEStudent> students = context.GetTable<T_XEStudent>();
string studentName = this.cmbStudentName.Text;
CurrentSelectedStudent = students.SingleOrDefault(m => m.StudentName.Equals(studentName));
currentPaper = CurrentSelectedStudent.T_XEPapers.SingleOrDefault();
private void btnSavePingYue_Click(object sender, EventArgs e)
{
T_XEComment com=currentPaper.T_XEComments.SingleOrDefault(m => m.CommentTeacherName.Equals(teacher.TeacherName));
//修改评语 数据库中友Comment记录
if (com!=null)
{
com.ReceiveScoreSelectSubject = Convert.ToInt32(this.cmbReceiveScoreSelectSubject.Text);
com.RecieveScoreComprehensiveSkill = Convert.ToInt32(this.cmbRecieveScoreComprehensiveSkill.Text);
com.RecieveScoreReferenceDocument = Convert.ToInt32(this.cmbRecieveScoreReferenceDocument.Text);
com.RecieveScoreWritingLevel = Convert.ToInt32(this.cmbRecieveScoreWritingLevel.Text);
com.RecieveScoreStudingLevel = Convert.ToInt32(this.cmbRecieveScoreStudingLevel.Text);
com.RecieveScoreFormat = Convert.ToInt32(this.cmbRecieveScoreFormat.Text);
com.CommentContent = this.txtBoxComment.Text;
if (teacherService.SavePingYue()) //修改记录后保存 调用public bool SaveChanges()方法
{
MessageBox.Show("修改评阅内容成功");
}
else
{
MessageBox.Show("修改评阅内容失败");
}
}
//增加评语
else
{
//跟对象必须做出修改 新添加的子对象才能被DataContext识别
com = new T_XEComment();
com.CommentTeacherName = teacher.TeacherName;
com.ReceiveScoreSelectSubject = Convert.ToInt32(this.cmbReceiveScoreSelectSubject.Text);
com.RecieveScoreComprehensiveSkill = Convert.ToInt32(this.cmbRecieveScoreComprehensiveSkill.Text);
com.RecieveScoreReferenceDocument = Convert.ToInt32(this.cmbRecieveScoreReferenceDocument.Text);
com.RecieveScoreWritingLevel = Convert.ToInt32(this.cmbRecieveScoreWritingLevel.Text);
com.RecieveScoreStudingLevel = Convert.ToInt32(this.cmbRecieveScoreStudingLevel.Text);
com.RecieveScoreFormat = Convert.ToInt32(this.cmbRecieveScoreFormat.Text);
com.CommentContent = this.txtBoxComment.Text;
currentPaper.T_XEComments.Add(com);//调用EntitySet的Add（）方法
if (teacherService.SavePingYue()) //调用public bool SaveChanges()方法
{
MessageBox.Show("增加评阅内容成功");
}
else
{
MessageBox.Show("增加评阅内容失败");
}
}
}
public bool SaveChanges()
{
try
{
ChangeSet set = context.GetChangeSet();
IList<object> updateSet = set.Updates;
IList<object> delelteSet= set.Deletes;
IList<object> insertSet = set.Inserts;
context.SubmitChanges();
}
catch (System.Exception ex)
{
return false;
}
return true;
}
[解决办法]
SavePingYue()方法是定义在teacherService 类内的
你需要将你当前的context传递到SavePingYue方法内
