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关于SqlDataAdapter的几个Command属性的疑问

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[已解决问题] 解决于 2011-02-01 20:40

http://topic.csdn.net/u/20071119/17/9316fdc5-5993-4720-a8e7-0d4ab5e28528.html 
上面的问题就是我碰到的

我想操作的是利用SqlDataAdapter的几个Command属性(InsertCommand,UpdateCommand,DeleteCommand)来更新数据库
代码:
SqlConnection conn = new SqlConnection(@"Data Source=.\sqlexpress;Initial Catalog=newsystem;Integrated Security=True");
  SqlDataAdapter da = new SqlDataAdapter("select * from comment", conn);
  //这里的构造函数直接实例化了SelectCommand所需要的SqlCommand了吧?
  DataSet ds = new DataSet("myds");
  da.FillSchema(ds, SchemaType.Source, "comment");
  da.Fill(ds, "comment");
  //接下来设置InsertCommand所需要的SqlCommand
SqlCommand incmd=new SqlCommand("insert into comment (****) values(****)",conn);
  da.InsertCommand = incmd;
  //接下来是更新到数据库
  da.Update(ds.Tables["comment"]);
  ds.Tables["comment"].AcceptChanges();
  可到数据库里一看,悲剧发生了:没有插入该条记录!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

网上一查:有些说要实例化SqlCommandBuilder,可我觉得我的InsertCommand所需要的SqlCommand都写好了,不需要这样吧!
SqlCommandBuilder好像只是适用于直接修改DataSet,由SqlCommandBuilder自动生成所需的SQL语句:

  SqlConnection conn = new SqlConnection(@"Data Source=.\sqlexpress;Initial Catalog=newsystem;Integrated Security=True");
  SqlDataAdapter da = new SqlDataAdapter("select * from comment", conn);
  SqlCommandBuilder cmdb = new SqlCommandBuilder(da);
  DataSet ds = new DataSet("myds");
  da.FillSchema(ds, SchemaType.Source, "comment");
  da.Fill(ds, "comment");
  ds.Tables["comment"].Rows[5]["content"] = "Can you help me???";
  da.Update(ds.Tables["comment"]);
  ds.Tables["comment"].AcceptChanges();

何塞穆里尼奥的主页 何塞穆里尼奥 | 初学一级 | 园豆:129
提问于:2010-11-27 14:30
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最佳答案
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public static SqlDataAdapter CreateCustomerAdapter( SqlConnection connection)
{
    SqlDataAdapter adapter = new SqlDataAdapter();

    // Create the SelectCommand.
    SqlCommand command = new SqlCommand("SELECT * FROM Customers " +
        "WHERE Country = @Country AND City = @City", connection);

    // Add the parameters for the SelectCommand.
    command.Parameters.Add("@Country", SqlDbType.NVarChar, 15);
    command.Parameters.Add("@City", SqlDbType.NVarChar, 15);

    adapter.SelectCommand = command;

    // Create the InsertCommand.
    command = new SqlCommand(
        "INSERT INTO Customers (CustomerID, CompanyName) " +
        "VALUES (@CustomerID, @CompanyName)", connection);

    // Add the parameters for the InsertCommand.
    command.Parameters.Add("@CustomerID", SqlDbType.NChar, 5, "CustomerID");
    command.Parameters.Add("@CompanyName", SqlDbType.NVarChar, 40, "CompanyName");

    adapter.InsertCommand = command;

    // Create the UpdateCommand.
    command = new SqlCommand(
        "UPDATE Customers SET CustomerID = @CustomerID, CompanyName = @CompanyName " +
        "WHERE CustomerID = @oldCustomerID", connection);

    // Add the parameters for the UpdateCommand.
    command.Parameters.Add("@CustomerID", SqlDbType.NChar, 5, "CustomerID");
    command.Parameters.Add("@CompanyName", SqlDbType.NVarChar, 40, "CompanyName");
    SqlParameter parameter = command.Parameters.Add(
        "@oldCustomerID", SqlDbType.NChar, 5, "CustomerID");
    parameter.SourceVersion = DataRowVersion.Original;

    adapter.UpdateCommand = command;

    // Create the DeleteCommand.
    command = new SqlCommand(
        "DELETE FROM Customers WHERE CustomerID = @CustomerID", connection);

    // Add the parameters for the DeleteCommand.
    parameter = command.Parameters.Add(
        "@CustomerID", SqlDbType.NChar, 5, "CustomerID");
    parameter.SourceVersion = DataRowVersion.Original;

    adapter.DeleteCommand = command;

    return adapter;
}

jasen.kin | 菜鸟二级 |园豆:248 | 2010-11-27 15:20
public static DataSet GetCustomerData(string dataSetName, string connectionString) { DataSet dataSet = new DataSet(dataSetName); using (SqlConnection connection = new SqlConnection(connectionString)) { SqlDataAdapter adapter = new SqlDataAdapter( "SELECT CustomerID, CompanyName, ContactName FROM dbo.Customers", connection); DataTableMapping mapping = adapter.TableMappings.Add("Table", "Customers"); mapping.ColumnMappings.Add("CompanyName", "Name"); mapping.ColumnMappings.Add("ContactName", "Contact"); connection.Open(); adapter.FillSchema(dataSet, SchemaType.Mapped); adapter.Fill(dataSet); return dataSet; } } 看官方资料 很多
jasen.kin | 园豆:248 (菜鸟二级) | 2010-11-27 15:23
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