/// <summary>
/// 获取操作符
/// </summary>
/// <param name="node">表达式</param>
/// <returns></returns>
internal static string GetOperator(this UnaryExpression node)
{
if (node is null)
{
return(string.Empty);
}
switch (node.NodeType)
{
case ExpressionType.Negate:
case ExpressionType.NegateChecked:
return("-");
case ExpressionType.UnaryPlus:
return("+");
case ExpressionType.Not:
return(node.IsBoolean() ? "NOT" : "~");
default:
return(string.Empty);
}
}