public static Expression Replace(Expression e,
IEnumerable <KeyValuePair <ParameterExpression, ParameterExpression> > paramList)
{
var item = new ParameterReplace(paramList);
return(item.Visit(e));
}
/// <summary>
/// 拼接两个 <paramref>
/// <name>System.Linq.Expression</name>
/// </paramref>，两个 <paramref>
/// <name>System.Linq.Expression</name>
/// </paramref> 的参数必须完全相同。
/// </summary>
/// <param name="left">左边的 <paramref>
/// <name>System.Linq.Expression</name>
/// </paramref> </param>
/// <param name="right">右边的 <paramref>
/// <name>System.Linq.Expression</name>
/// </paramref> </param>
/// <param name="func">表达式拼接的具体逻辑</param>
/// <returns>拼接完成的System.Linq.Expression</returns>
private static LambdaExpression MakeBinary(this LambdaExpression left, LambdaExpression right,
Func <Expression, Expression, Expression> func)
{
var data = Combinate(right.Parameters, left.Parameters).ToArray();
right = ParameterReplace.Replace(right, data) as LambdaExpression;
Debug.Assert(right != null, "right != null");
return(Expression.Lambda(func(left.Body, right.Body), left.Parameters.ToArray()));
}