/// <summary> /// 创建参数 SQL 表达式 /// </summary> /// <param name="parameter">参数表达式</param> /// <returns>该参数在 SQL 语句中引用的形式</returns> public abstract string CreateParameterExpression( ParameterExpression parameter );
/// <summary>
/// 创建 TemplateExpression 对象
/// </summary>
/// <param name="template">模版</param>
/// <param name="parameters">参数列表</param>
public TemplateExpression( string template, params object[] parameters )
{
Template = template.Replace( "{...}", ParseParameterListSymbol( parameters.Length ) );
Parameters = parameters.Select( item =>
{
var partial = item as ITemplatePartialExpression;
if ( partial == null )
partial = new ParameterExpression( item );
return partial;
} ).ToArray();
var maxIndex = FormatRegexNum.Matches( Template ).Cast<Match>().Select( m => int.Parse( m.Groups["index"].Value ) ).Max();
if ( maxIndex >= Parameters.Length )
throw new IndexOutOfRangeException();
}
public SqlParameter CreateParameter( ParameterExpression expression, string name )
{
return new SqlParameter( name, expression.Value ?? DBNull.Value );
}
public override string CreateParameterExpression( ParameterExpression expression )
{
lock ( sync )
{
var name = "@Param" + list.Count;
var parameter = CreateParameter( expression, name );
list.Add( parameter );
return name;
}
}
public override string CreateParameterExpression( ParameterExpression parameter )
{
throw new NotImplementedException();
}