用C#做二次开发，在创建一个长方体时遇到的问题，急需解决，谢谢

footballboy

public void create_block()
! Y! m5 ^) W( m- ~, ?6 H    {
        UFModl uf_modl = new UFModl();
# G5 e3 u9 Q# u6 f  T        FeatureSigns featureSign;
        featureSign = FeatureSigns.Nullsign;
        double[] corner_pt = { 0, 0, 0 };
        string[] edge_len = { "50", "50", "50" };
3 f5 r" w0 c. q& u8 I/ V3 h! a3 A        Tag tag;
, ?/ U1 ?1 n1 u% Y; M        uf_modl.CreateBlock1(featureSign, corner_pt, edge_len, out tag);
    }
, A: I6 C& @. j+ w6 K" u2 M2 q
在创建UFModl类的实例时，有错误，提示为The type 'NXOpen.UF.UFModl' has no constructors defined