这是表格
用户
UserId
UserName
Password
EmailAddress
还有代码..
public void ChangePassword(int userId, string password){
//code to update the password..
}
这是表格
用户
UserId
UserName
Password
EmailAddress
还有代码..
public void ChangePassword(int userId, string password){
//code to update the password..
}
当前回答
您可以告诉EF哪些属性必须以这种方式更新:
public void ChangePassword(int userId, string password)
{
var user = new User { Id = userId, Password = password };
using (var context = new ObjectContext(ConnectionString))
{
var users = context.CreateObjectSet<User>();
users.Attach(user);
context.ObjectStateManager.GetObjectStateEntry(user)
.SetModifiedProperty("Password");
context.SaveChanges();
}
}
其他回答
您可以告诉EF哪些属性必须以这种方式更新:
public void ChangePassword(int userId, string password)
{
var user = new User { Id = userId, Password = password };
using (var context = new ObjectContext(ConnectionString))
{
var users = context.CreateObjectSet<User>();
users.Attach(user);
context.ObjectStateManager.GetObjectStateEntry(user)
.SetModifiedProperty("Password");
context.SaveChanges();
}
}
结合几项建议,我提出如下:
async Task<bool> UpdateDbEntryAsync<T>(T entity, params Expression<Func<T, object>>[] properties) where T : class
{
try
{
var entry = db.Entry(entity);
db.Set<T>().Attach(entity);
foreach (var property in properties)
entry.Property(property).IsModified = true;
await db.SaveChangesAsync();
return true;
}
catch (Exception ex)
{
System.Diagnostics.Debug.WriteLine("UpdateDbEntryAsync exception: " + ex.Message);
return false;
}
}
被
UpdateDbEntryAsync(dbc, d => d.Property1);//, d => d.Property2, d => d.Property3, etc. etc.);
或通过
await UpdateDbEntryAsync(dbc, d => d.Property1);
或通过
bool b = UpdateDbEntryAsync(dbc, d => d.Property1).Result;
public async Task<bool> UpdateDbEntryAsync(TEntity entity, params Expression<Func<TEntity, object>>[] properties)
{
try
{
this.Context.Set<TEntity>().Attach(entity);
EntityEntry<TEntity> entry = this.Context.Entry(entity);
entry.State = EntityState.Modified;
foreach (var property in properties)
entry.Property(property).IsModified = true;
await this.Context.SaveChangesAsync();
return true;
}
catch (Exception ex)
{
throw ex;
}
}
虽然我已经晚了,但这就是我所做的,我花了一段时间去寻找一个让我满意的解决方法;当你通过“白名单”概念显式地定义它们是什么时,这只会为更改的字段生成一个UPDATE语句,这更安全,可以防止web表单注入。
摘自我的ISession数据存储库:
public bool Update<T>(T item, params string[] changedPropertyNames) where T
: class, new()
{
_context.Set<T>().Attach(item);
foreach (var propertyName in changedPropertyNames)
{
// If we can't find the property, this line wil throw an exception,
//which is good as we want to know about it
_context.Entry(item).Property(propertyName).IsModified = true;
}
return true;
}
如果您愿意,可以将其封装在try. catch中,但我个人希望调用者了解此场景中的例外情况。
它将以类似这样的方式被调用(对我来说,这是通过ASP。NET Web API):
if (!session.Update(franchiseViewModel.Franchise, new[]
{
"Name",
"StartDate"
}))
throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.NotFound));
我一直在寻找同样的方法,最后我找到了解决方案
using (CString conn = new CString())
{
USER user = conn.USERs.Find(CMN.CurrentUser.ID);
user.PASSWORD = txtPass.Text;
conn.SaveChanges();
}
相信我,这对我很有效。