Change tracking in entity framework

Question

0.00/5 (No votes)

See more:

Hi Everyone,
I have a problem in Change Tracking in entity framework in modified sate
I have used such as this code

C#

var modifiedEntities = ChangeTracker.Entries()
    .Where(p => p.State == EntityState.Modified).ToList();

var now = DateTime.UtcNow;

foreach (var change in modifiedEntities)
{
    var entityName = change.Entity.GetType().Name;
    foreach (var prop in change.OriginalValues.PropertyNames)
    {
        var originalValue = change.OriginalValues[prop].ToString();
        var currentValue = change.CurrentValues[prop].ToString();
        if (originalValue != currentValue) //Only create a log if the value changes
        {
            //Create the Change Log
        }
    }

The debugger comes into if condition but my problem is the field has been modified but this code could not find it but it knows it has modified. Because it comes into the inner part. How can I get the previous value..
Thanks

What I have tried:

I implemented its code but it could get the previous value.

Posted 29-Sep-20 20:22pm

Moses_k

Updated 29-Sep-20 22:12pm

Richard Deeming

v2

Add a Solution

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Richard Deeming · Accepted Answer · 2020-09-29T22:13:00

Try:

C#

var modifiedEntities = ChangeTracker.Entities().Where(p => p.State == EntityState.Modified).ToList();
foreach (var change in modifiedEntities)
{
    var entityName = change.Entity.GetType().Name;
    foreach (string propertyName in change.OriginalValues.PropertyNames)
    {
        if (change.Property(propertyName) is DbPropertyEntry property && property.IsModified)
        {
            object originalValue = property.OriginalValue;
            object currentValue = proeprty.CurrentValue;
            // Create the change log...
        }
    }
}