Question

我正在尝试使用Dapper更新一行，但我在更新语句中指定参数时遇到错误

An exception of type 'System.InvalidOperationException' occurred in IBM.Data.DB2.iSeries.dll but was not handled in user code
Additional information: Not enough parameters specified.  The command
requires 3 parameter(s), but only 0 parameter(s) exist in the
parameter collection.

Repository.cs

public void Update(Movie movie)
{
      var sql = "UPDATE myDB.movies set title=?, genre=? where Id=?";
      db.Execute(sql, new 
               {   movie.Title, 
                   movie.Genre, 
                   movie.ID 
               });
}

Movie.cs

public class Movie
{
    public int ID { get; set; }
    [Required]
    public string Title { get; set; }

    [Required]
    [Display(Name="Release Date")]
    [DisplayFormat(DataFormatString="{0:dd/MM/yyyy}", ApplyFormatInEditMode=true)]
    public DateTime ReleaseDate { get; set; }

    [Required]
    public string Genre { get; set; }
    public decimal Price { get; set; }
}

我正在使用iDB2Connection来访问IBM ISeries数据库。

Answer 1

解决方法1

我所做的是命名参数，使得无论Dapper的字母顺序如何，它们的顺序都保持不变。

public void Update(Movie movie)
{
  var sql = "UPDATE myDB.movies set title=@param1, genre=@param2 where ID=@param3";
  db.Execute(sql, new { param1 = movie.Title, param2 = movie.Genre, param3 = movie.ID });
}

如果有人知道更好的解决方案。请在这个帖子中发帖。

Answer 2

在Repository.cs文件中尝试这样做

public void Update(Movie movie)
{
      var sql = "UPDATE myDB.movies set title=:Title, genre=:Genre where Id=:ID";
      db.Execute(sql, new 
               {  
                  Title = movie.Title, 
                  Genre = movie.Genre, 
                  ID = movie.ID 
               });
}

无法使用Dapper运行更新语句（参数错误）

2 个答案: