Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
487 views
in Technique[技术] by (71.8m points)

asp.net mvc 3 - Nullable property to entity field, Entity Framework through Code First

Using the data annotation Required like so:

[Required]
public int somefield {get; set;}

Will set somefield to Not Null in database, How can I set somefield to allow NULLs?, I tried setting it through SQL Server Management Studio but Entity Framework set it back to Not Null.

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Answer

0 votes
by (71.8m points)

Just omit the [Required] attribute from the string somefield property. This will make it create a NULLable column in the db.

To make int types allow NULLs in the database, they must be declared as nullable ints in the model:

// an int can never be null, so it will be created as NOT NULL in db
public int someintfield { get; set; }

// to have a nullable int, you need to declare it as an int?
// or as a System.Nullable<int>
public int? somenullableintfield { get; set; }
public System.Nullable<int> someothernullableintfield { get; set; }

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...