Can I return the 'id' field after a LINQ insert?
When I enter an object into the DB with Linq-to-SQL can I get the id that I just inserted without making another db call? I am assuming this is pretty easy, I just don't know how.
Solution 1:
After you commit your object into the db the object receives a value in its ID field.
So:
myObject.Field1 = "value";
// Db is the datacontext
db.MyObjects.InsertOnSubmit(myObject);
db.SubmitChanges();
// You can retrieve the id from the object
int id = myObject.ID;
Solution 2:
When inserting the generated ID is saved into the instance of the object being saved (see below):
protected void btnInsertProductCategory_Click(object sender, EventArgs e)
{
ProductCategory productCategory = new ProductCategory();
productCategory.Name = “Sample Category”;
productCategory.ModifiedDate = DateTime.Now;
productCategory.rowguid = Guid.NewGuid();
int id = InsertProductCategory(productCategory);
lblResult.Text = id.ToString();
}
//Insert a new product category and return the generated ID (identity value)
private int InsertProductCategory(ProductCategory productCategory)
{
ctx.ProductCategories.InsertOnSubmit(productCategory);
ctx.SubmitChanges();
return productCategory.ProductCategoryID;
}
reference: http://blog.jemm.net/articles/databases/how-to-common-data-patterns-with-linq-to-sql/#4