Question

我必须在不使用存储过程的情况下执行大量SQL插入。

对于大类，插入字符串变得很大，所以我考虑构建一个通用的插入函数来处理它在传入一个对象时。我在下面写的内容有效，但它并不理想，因为（1）我必须指定所有可能的数据类型，（2）我必须将所有值转换回字符串以构建插入字符串，我宁愿使用参数值。

我只想要一个函数，我将它传递给一个对象类，函数将对象的值插入到数据库中（假设表中的所有列名都与对象的属性名匹配）

非常感谢任何想法，谢谢。

public static IEnumerable<KeyValuePair<string, T>> PropertiesOfType<T>(object obj)
{
    return from p in obj.GetType().GetProperties()
           where p.PropertyType == typeof(T)
           select new KeyValuePair<string, T>(p.Name, (T)p.GetValue(obj, null));
}

public string InsertString(string _table, object _class)
{
    Dictionary<string, string> returnDict = new Dictionary<string, string>();
    StringBuilder sb = new StringBuilder();
    foreach (var property in PropertiesOfType<DateTime>(_class))
        returnDict.Add(property.Key, property.Value.ToString("yyyy-MM-dd HH:mm:ss"));
    foreach (var property in PropertiesOfType<string>(_class))
        returnDict.Add(property.Key, property.Value);
    foreach (var property in PropertiesOfType<int>(_class))
    {
        if (property.Key == "Key")
            continue;
        returnDict.Add(property.Key, property.Value.ToString());
    }            
    foreach (var property in PropertiesOfType<bool>(_class))
    {
        if (property.Value)
            returnDict.Add(property.Key, "1");
        else
            returnDict.Add(property.Key, "0");
    }
    foreach (var property in PropertiesOfType<decimal>(_class))
        returnDict.Add(property.Key, property.Value.ToString());
    foreach (var property in PropertiesOfType<long>(_class))
        returnDict.Add(property.Key, property.Value.ToString());
    if (returnDict.Count == 1)
    {
        sb.Append(string.Format("INSERT INTO [{0}] ({1}) VALUES ('{2}')", _table, returnDict.ElementAt(0).Key, returnDict.ElementAt(0).Value));
    }
    else
    {
        for (int i = 0; i < returnDict.Count; i++)
        {
            if (i == 0)
                sb.Append(string.Format("INSERT INTO [{0}] ({1}, ", _table, returnDict.ElementAt(i).Key));
            else if (i == returnDict.Count - 1)
                sb.Append(string.Format("{0}) ", returnDict.ElementAt(i).Key));
            else
                sb.Append(string.Format("{0}, ", returnDict.ElementAt(i).Key));
        }
        for (int i = 0; i < returnDict.Count; i++)
        {
            if (i == 0)
                sb.Append(string.Format("VALUES ('{0}', ", returnDict.ElementAt(i).Value));
            else if (i == returnDict.Count - 1)
                sb.Append(string.Format("'{0}')", returnDict.ElementAt(i).Value));
            else
                sb.Append(string.Format("'{0}', ", returnDict.ElementAt(i).Value));
        }
    }        
    return sb.ToString();
}



string query = InsertString(_table, _obj);

Answer 1

我已经设法找到一种方法来做到这一点，我很高兴非常高兴，不需要任何外部库或框架。

基于@ HardikParmar的建议我构建了一个将类对象转换为数据表的新过程，然后将所有相关的数据类型存储为列。

然后使用类对象在结构化数据表中添加一行。

现在你有一行数据表有一行值。

然后我创建一个PARAMATERIZED插入语句。然后在我的命令文本中，我将值添加到参数中。

几乎干净，总是有改进的余地。

//this function creates the datatable from a specified class type, you may exclude properties such as primary keys public DataTable ClassToDataTable<T>(List<string> _excludeList = null) { Type classType = typeof(T); List<PropertyInfo> propertyList = classType.GetProperties().ToList(); DataTable result = new DataTable(classType.Name); foreach (PropertyInfo prop in propertyList) { if (_excludeList != null) { bool toContinue = false; foreach (string excludeName in _excludeList) { if (excludeName == prop.Name) { toContinue = true; break; } } if (toContinue) continue; } result.Columns.Add(prop.Name, prop.PropertyType); } return result; } //add data to the table public void AddRow(ref DataTable table, object data) { Type classType = data.GetType(); string className = classType.Name; if (!table.TableName.Equals(className)) { throw new Exception("DataTableConverter.AddRow: " + "TableName not equal to className."); } DataRow row = table.NewRow(); List<PropertyInfo> propertyList = classType.GetProperties().ToList(); foreach (PropertyInfo prop in propertyList) { foreach (DataColumn col in table.Columns) { if (col.ColumnName == prop.Name) { if (table.Columns[prop.Name] == null) { throw new Exception("DataTableConverter.AddRow: " + "Column name does not exist: " + prop.Name); } row[prop.Name] = prop.GetValue(data, null); } } } table.Rows.Add(row); } //creates the insert string public string MakeInsertParamString(string _tableName, DataTable _dt, string _condition=null) { StringBuilder sb = new StringBuilder(); sb.Append(string.Format("INSERT INTO [{0}] (", _tableName)); for (int i = 0; i < _dt.Columns.Count; i++) { sb.Append(string.Format("{0}", _dt.Columns[i].ColumnName)); if (i < _dt.Columns.Count - 1) sb.Append(", "); } sb.Append(") VALUES ("); for (int i = 0; i < _dt.Columns.Count; i++) { sb.Append(string.Format("@{0}", _dt.Columns[i].ColumnName)); if (i < _dt.Columns.Count - 1) sb.Append(", "); } sb.Append(")"); if (!string.IsNullOrEmpty(_condition)) sb.Append(" WHERE " + _condition); return sb.ToString(); } //inserts into the database public string InsertUsingDataRow(string _tableName, DataTable _dt, string _condition = null) { try { using (SQLiteConnection conn = new SQLiteConnection(_dbPath)) { string query = MakeInsertParamString(_tableName, _dt, _condition); SQLiteCommand cmd = new SQLiteCommand(query, conn); foreach (DataColumn col in _dt.Columns) { var objectValue = _dt.Rows[0][col.ColumnName]; cmd.Parameters.AddWithValue("@" + col.ColumnName, objectValue); } conn.Open(); cmd.ExecuteNonQuery(); conn.Close(); } //return MakeInsertParamString(_tableName, _dt, _condition); return "Success"; } catch (Exception ex) { return ex.Message; } }

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