小编use*_*704的帖子

如何从Comp表中获取company_name的值并将其存储在comboBox中？

这是我从数据库获取值并将其存储在组合框中的初始代码:

string Sql = "select company_name from JO.dbo.Comp";
SqlConnection conn = new SqlConnection(connString);
SqlCommand cmd = new SqlCommand(Sql, conn);
cmd.CommandType = CommandType.StoredProcedure;
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds);
for (int i = 0; i < ds.Tables[0].Rows.Count; i++)
  comboBox1.Items.Add(ds.Tables[0].Rows[i][0].ToString());

它指出da.fill(ds)并说"Could not locate entry in sysdatabases for database 'select company_name from JO'.找不到具有该名称的条目.确保输入的名称正确."

希望你的回复谢谢!

当我运行这段代码时，我在 catch（异常 e）部分出现错误，我不知道为什么，编译器说“不能在此范围内声明名为 'e' 的局部变量，因为它会给 ' 赋予不同的含义e'，它已经在“父级或当前”范围中使用来表示其他内容”

        try
        {

            //Form Query which will insert Company and will output generated id 
            myCommand.CommandText = "Insert into Comp(company_name) Output Inserted.ID VALUES (@company_name)";
            myCommand.Parameters.AddWithValue("@company_name", txtCompName);
            int companyId = Convert.ToInt32(myCommand.ExecuteScalar());

            //For the next scenario, in case you need to execute another command do it before committing the transaction

            myTrans.Commit();

            //Output Message in message box
            MessageBox.Show("Added", "Company Added with id" + companyId, MessageBoxButtons.OK, MessageBoxIcon.Information);

        }

        catch (Exception e)
        {
            try
            {
                myTrans.Rollback();
            }
            catch (SqlException …