使所有字符串从实体框架数据库大写

要解决此问题，您可以尝试通过循环模型和属性来配置HasConversion 。

尝试如下代码：

public class ApplicationDbContext : IdentityDbContext
{
    public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options)
        : base(options)
    {
    }
    public DbSet<Product> Products { get; set; }
    public DbSet<Tag> Tags { get; set; }
    protected override void OnModelCreating(ModelBuilder builder)
    {
        base.OnModelCreating(builder);
        var converter = new ValueConverter<string, string>(
                v => v,
                v => v.ToUpper());
        foreach (var entityType in builder.Model.GetEntityTypes())
        {
            foreach (var property in entityType.GetProperties())
            {
                if (property.ClrType == typeof(string))
                {
                    builder.Entity(entityType.Name)
                           .Property(property.Name)
                           .HasConversion(converter);
                }
            }
        }
    }
}