public Class28()
    {
        Class2.XRoAsQdzvBk9W();
        this.string_0 = "";
        this.string_1 = "0";
        this.string_2 = "0";
        this.string_3 = "";
        this.string_4 = "";
  line 8 -  base..ctor(); error -identifier expexted
    }

how to remove the error at  line 8 and 

basicaly i have decompile a file and trying to rebuild a proggram but not able to clearly know how to remove this err actually why here method base..ctor is being called?

The base class of Class28 is being called. Generally that would look like:

public class Class28 : public SomeOtherClass
{
    public Class28()
        : base()
    {
    }
}

 

You better deobfuscate the program first