错误：名称空间不能直接包含诸如字段或方法之类的成员

Question

I'm new to C# and I'm having trouble solving this error can anyone help me please? This script is to delete an un-needed shortcut then install a new program if it hasn't been installed already.

using System;
using WindowsInstaller;


string startMenuDir = Environment.GetFolderPath(Environment.SpecialFolder.StartMenu);
string shortcutold = Path.Combine(startMenuDir, @"Ohal\TV AMP (Windows XP Mode).lnk");
if (File.Exists(shortcutold))
File.Delete(shortcutold);


string startMenuDir = Environment.GetFolderPath(Environment.SpecialFolder.StartMenu);
string shortcut = Path.Combine(startMenuDir, @"Ohal\TV AMP.lnk");
if (File.Exists(shortcut))
{
    Console.WriteLine("Already installed...");
}
else
{
Type type = Type.GetTypeFromProgID("WindowsInstaller.Installer");
            Installer installer = (Installer)Activator.CreateInstance(type);
            installer.InstallProduct(@"Y:\LibSetup\TVAMP313\TVAmp v3.13.msi");
}

Answer 1

Your code should be in a class and then a method. You can't have code under namespace. Something like following.

using System;
using WindowsInstaller;

class MyClass //Notice the class 
{
 //You can have fields and properties here

    public void MyMethod() // then the code in a method
    {
        string startMenuDir = Environment.GetFolderPath(Environment.SpecialFolder.StartMenu);
        string shortcutold = Path.Combine(startMenuDir, @"Ohal\TV AMP (Windows XP Mode).lnk");
        if (File.Exists(shortcutold))
            File.Delete(shortcutold);
       // your remaining code .........


    }
}

Answer 2

As Habib says, you need to put code in methods, constructors etc. In this case if the code you want is just what you want as the entry point, you just need:

using System;
using WindowsInstaller;

class Program
{
    // Or static void Main(string[] args) to use command line arguments
    static void Main()
    {
        string startMenuDir = ...;
        string shortcutold = ...;
        // Rest of your code
    }
}

Basically the Main method is the entry point for a stand-alone C# program.

Of course, if your code is meant to be a plug-in for something else, you may need to just implement an interface or something similar. Either way, you'll have to have your code in members rather than just "bare".

Answer 3

Most likely this is what you intended to do:

using System;
using WindowsInstaller;

namespace DataImporter
{
    class Program
    {
        static void Main(string[] args)
        {

            string startMenuDir = Environment.GetFolderPath(Environment.SpecialFolder.StartMenu);
            string shortcutold = Path.Combine(startMenuDir, @"Ohal\TV AMP (Windows XP Mode).lnk");
            if (File.Exists(shortcutold))
            File.Delete(shortcutold);


            string startMenuDir = Environment.GetFolderPath(Environment.SpecialFolder.StartMenu);
            string shortcut = Path.Combine(startMenuDir, @"Ohal\TV AMP.lnk");
            if (File.Exists(shortcut))
            {
                Console.WriteLine("Already installed...");
            }
            else
            {
            Type type = Type.GetTypeFromProgID("WindowsInstaller.Installer");
                        Installer installer = (Installer)Activator.CreateInstance(type);
                        installer.InstallProduct(@"Y:\LibSetup\TVAMP313\TVAmp v3.13.msi");
            }
        }
    }
}

Answer 4

您的Method现在必须在类中这是在名称空间中，您必须在此Namespace中声明一个类，然后在该类中声明方法