創建動態SQL DbParameter值

Question

第一次用戶 - 希望這是正確的格式：

我想知道我是否可以在ParamaterName上創建SQL DbParameter值。

我目前的代碼是：

DbCommand dbCommand = SqlDb.GetStoredProcCommand(uspCommand);
DbParameter ProcessedFileName = dbCommand.CreateParameter();
ProcessedFileName.DbType = DbType.String;
ProcessedFileName.ParameterName = "@FileName";
ProcessedFileName.Value = pstrProcessedFileName;
dbCommand.Parameters.Add(ProcessedFileName);

我想補充一下：

ProcessedFileName.ParameterName = "@FileName1";
ProcessedFileName.ParameterName = "@FileName2";
ProcessedFileName.ParameterName = "@FileName3";
ProcessedFileName.ParameterName = "@FileName4";

來自數組的@FileNames 。

Answer 1

這樣的事情應該有效：

DbCommand dbCommand = SqlDb.GetStoredProcCommand(uspCommand);

foreach(String param in MyParameters)
{
   DbParameter ProcessedFileName = dbCommand.CreateParameter();
   ProcessedFileName.DbType = DbType.String;
   ProcessedFileName.ParameterName = param;
   ProcessedFileName.Value = pstrProcessedFileName;
   dbCommand.Parameters.Add(ProcessedFileName);
}

Answer 2

最好的方法是把它們放在字典中，因為你也需要價值

Dictionary<string, string> params = new Dictionary<string,string>();

並根據需要添加許多

params.Add("@FileName1", "my_filename")

等等...

接着

foreach(var param in params)
   dbCommand.Parameters.AddWithValue(param.Key, param.Value);

Answer 3

重構為DbCommand的擴展，fieldName也沒有@，因此你需要傳遞@或：前綴，並將fieldValue設置為對象類型（不僅僅是字符串）。

public static class DbCommandExtensions
{
    public static void AddParam(this DbCommand dbCommand, string fieldName, object fieldValue)
    {
        string fieldNameParameter = fieldName;

        DbParameter dbParameter = dbCommand.CreateParameter();
        dbParameter.ParameterName = fieldNameParameter;
        dbParameter.Value = fieldValue;
        dbCommand.Parameters.Add(dbParameter);
    }
}

Answer 4

創建動態SQL DbParameter值

當您要創建有動態數據庫的項目時，這非常有用，或者將來您可能要遷移/切換數據庫。

這是一步一步的解決方案

步驟1）創建參數結構

  public struct Parameter
    {
        public string ParameterName { get; set; }
        public ParameterDirection Direction { get; set; }
        public DbType DbType { get; set; }
        public object Value { get; set; }
        public string SourceColumn { get; set; }
        public int Size { get; set; }
    }

步驟2）創建數據庫處理類

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data.SqlClient;
using System.Data;
using System.Configuration;
using System.Data.Common;
using MySql.Data.MySqlClient;
using MySql.Data;
using Oracle.DataAccess;
using Oracle.DataAccess.Client;

 public class DBManagement  
    {
        string connectionStr;
        DbConnection con;
        DbCommand cmd;
        DbDataAdapter AD;
        DataSet ds;
        DbParameter[] sp;
        IDBManagement Iobj = null;
        public DBManagement()
        {
            this.Initialize();
        }

 void Initialize()
        {
            try
            {

                switch (ConfigurationManager.AppSettings["ActiveDatabase"].ToUpper())
                {
                    case "MSSQL":
                        connectionStr = ConfigurationManager.ConnectionStrings["MSSQLConnectionString"].ConnectionString;
                        con = new SqlConnection();
                        cmd = new SqlCommand();
                        AD = new SqlDataAdapter();
                        break;
                    case "ORACLE":
                        connectionStr = ConfigurationManager.ConnectionStrings["OracleConnectionString"].ConnectionString;
                        con = new OracleConnection();
                        cmd = new OracleCommand();
                        AD = new OracleDataAdapter();
                        break;
                    case "MYSQL":
                        connectionStr = ConfigurationManager.ConnectionStrings["MYSQLConnectionString"].ConnectionString;
                        con = new MySqlConnection();
                        cmd = new MySqlCommand();
                        AD = new MySqlDataAdapter();
                        break;
                    default:

                        break;
                }

                con.ConnectionString = connectionStr;
                cmd.Connection = con;
            }
            catch (Exception ex)
            {

            }
        }

        public DataSet ExecuteProcedure(string procName, CommandType cmdType, Parameter[] DBParameters = null)
        {
            try
            {
                cmd.CommandText = procName;
                cmd.CommandType = cmdType;

                cmd.Parameters.Clear();

                if (DBParameters != null && DBParameters.Length > 0)
                { 
                    sp = DBParameters.ToParamerArray(cmd);  
                    cmd.Parameters.AddRange(sp); 
                }
                ds = new DataSet();
                AD.SelectCommand = cmd;
                AD.Fill(ds);
                return ds;
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }
}

步驟3）按照數據庫轉換參數

public static partial class GlobalExtensionFunctions 
    {
        public static DbParameter[] ToParamerArray(this Parameter[] parameters,DbCommand cmd)
        {
            DbParameter[] sp = new DbParameter[parameters.Length]; 
            int i = 0;
            foreach (Parameter parameter in parameters)
            {
               // DbParameter p = cmd.CreateParameter();
                sp[i] = cmd.CreateParameter();
                sp[i].ParameterName = parameter.ParameterName;
                sp[i].Value = parameter.Value;
                sp[i].Direction = string.IsNullOrEmpty(Convert.ToString(parameter.Direction))  || parameter.Direction==0 ? ParameterDirection.Input : parameter.Direction;
                sp[i].DbType = parameter.DbType;
                sp[i].SourceColumn = parameter.SourceColumn;
                sp[i].Size = parameter.Size;
                i++;
            }
            return sp;
        }
    }

步驟4）獲取數據

 DBManagement c = new DBManagement();
public DataSet GetGetTestList(int testId)
        {
            Parameter[] p = new Parameter[1]; 

            p[0].ParameterName = "@TestId";
            p[0].Value = testId;
            p[0].DbType = DbType.Int32;

            return c.ExecuteProcedure(Procedures.TestDetails, CommandType.StoredProcedure,p);
        }

現在使用數據集或數據表，享受！ :)

Answer 5

安倍 - 謝謝 - 你讓我朝着正確的方向前進。 這是我最終做的事情：

在我的foreach循環中，我正在調用我的方法：

foreach (DataRow row in GlobalClass.NAVdataTable.Rows)
  {
    GlobalClass.AddToDbCommand(ref dBCommand, row["FieldName"].ToString(), row["Value"].ToString());

    connection.Open();
    SqlDb.ExecuteNonQuery(dBCommand);
    connection.Close();
    dBCommand.Parameters.Clear();
  }

然后我的AddToDbCommand方法包含：

public static void AddToDbCommand(ref DbCommand dbCommand, string FieldName, string FieldValue)
    {
        string FieldNameParameter = "@" + FieldName;
        DbParameter dbParameter = dbCommand.CreateParameter();
        dbParameter.ParameterName = FieldNameParameter; 
        dbParameter.Value = FieldValue;
        dbCommand.Parameters.Add(dbParameter);
    }