无法将类型'string'隐式转换为'System.Type'

Question

I am trying to build a contact managers program in a console application using a list to store and display the data. I need to view a report that displays a summary of contacts available and then have a menu to allow the user to interact with the program. I have a method to create a list with data and a contact object but I keep getting the error Cannot implicitly convert type 'string' to 'System.Type' in my createContact() method. I am not sure how to fix this.

any guidance would be appreciated

     public static void createContact()
    {
        Contact c1 = new Contact();
        Console.WriteLine("\nGetFirstName");
        c1.GetFirstName = Console.ReadLine();
        Console.WriteLine("\nGetLastName");
        c1.GetLastName = Console.ReadLine();
        Console.WriteLine("\nGetEmailAddress");
        c1.GetEmailAddress = Console.ReadLine();
        Console.WriteLine("\nGetPhoneNumber");
        c1.GetPhoneNumber = Console.ReadLine();
        Console.WriteLine("\nContactTypes");
        c1.ContactTypes = Console.ReadLine();

        //Create more contacts...

        //Add all contacts here
        ContactCollection contactList = new ContactCollection();
        contactList.Add(c1);

        //Loop through list
        foreach (Contact c in contactList)
        {
            Console.WriteLine(c.GetFirstName);
            Console.WriteLine(c.GetLastName);
            Console.WriteLine(c.GetEmailAddress);
            Console.WriteLine(c.GetPhoneNumber);
           // error line
            Console.WriteLine(c.ContactTypes);

        }

        Console.ReadLine();

    }

Here is my contact class

class Contact
{

    //private member variables
    private String _firstName;
    private String _lastName;
    private Type _contactTypes;
    private String _phoneNumber;
    private String _emailAddress;




    //Public constructor that takes five arguments
    public Contact()
    {
        //Call the appropriate setter (e.g. FirstName) to set the member variable value
        /*GetFirstName = firstName;
        GetLastName = lastName;
        ContactTypes = contactTypes;
        GetPhoneNumber = phoneNumber;
        GetEmailAddress = emailAddress;*/

    }


    /*********************************************************************
     * Public accessors used to get and set private member variable values
     *********************************************************************/
    //Public  ContactTypes accessor
    public Type ContactTypes
    {
        get
        {
            //Return member variable value
            return _contactTypes;
        }
        set
        {
              //Validate value and throw exception if necessary
            if (value == null)
                throw new Exception("ContactType must have a value");
            else
                //Otherwise set member variable value*/
                _contactTypes = value;
        }
    }
    enum ContactTypesEnum { Family, Friend, Professional }
    //Public FirstName accessor: Pascal casing
    public String GetFirstName
    {
        get
        {
            //Return member variable value
            return _firstName;
        }
        set
        {
            //Validate value and throw exception if necessary
            if (value == "")
                throw new Exception("First name must have a value");
            else
                //Otherwise set member variable value
                _firstName = value;
        }
    }

    //Public LastName accessor: Pascal casing
    public String GetLastName
    {
        get
        {
            //Return member variable value
            return _lastName;
        }
        set
        {
            //Validate value and throw exception if necessary
            if (value == "")
                throw new Exception("Last name must have a value");
            else
                //Otherwise set member variable value
                _lastName = value;
        }
    }



    //Public PhoneNumber accessor
    public String GetPhoneNumber
    {
        get
        {
            //Return member variable value
            return _phoneNumber;
        }
        set
        {
            bool isValid = Regex.IsMatch(value, @"/d{3}-/d{3}-/d{4}"); 
            //Validate value and throw exception if necessary
            if (value == "")
                throw new Exception("PhoneNumber must have a value");
            else
                //Otherwise set member variable value
                _phoneNumber = value;
        }
    }



    //Public Email accessor
    public String GetEmailAddress
    {
        get
        {
            //Return member variable value
            return _emailAddress;
        }
        set
        {
            //Validate value and throw exception if necessary
            if (value == "")
                throw new Exception("EmailAddress must have a value");
            else
                //Otherwise set member variable value
                _emailAddress = value;
        }
    }

}

Answer 1

确保您的联系人类属性（GetFirstName，GetLastName等）是字符串，或将input（Console.ReadLine（））值转换为所需的类型。

Answer 2

Console.ReadLine() just returns a string. If you want to create any object ie: ContactTypes you should create its instance by using that string.

ContactTypes should be an enum not a Type.

public Type ContactTypes should be public ContactTypes ContactTypes .

enum ContactTypesEnum { Family, Friend, Professional } should be enum ContactTypes { Family, Friend, Professional }

You should do something like below. Last parameter is ignoreCare which I've set to true .

c1.ContactTypes = (ContactTypes) Enum.Parse(typeof(ContactTypes ), Console.ReadLine(), true);

Answer 3

I think you miss-typed the Contact class

Perhaps

public Type ContactTypes

should be like this instead:

public ContactTypesEnum Type 

And

private Type _contactTypes;

like this:

private ContactTypesEnum _contactTypes;

Answer 4

Console.ReadLine() returns a string. What you want is the type which gets returned from Readline().

c1.ContactTypes = Console.ReadLine().GetType();

But this doesnt make any sense, because Console.Readline will always be "Sytem.String". You might have to Convert the returned value (string) to the object you prefer.

var currString = Console.ReadLine().GetType();
object currObject = currString;
if(//Check if numeric for ex.)
{
    currObject = Convert.ToInt32(currString);     
}
//Do some more validation
//Now getType()
c1.ContactTypes = Console.ReadLine();

Also see CharithJ and Chandrashekar Jupalli answer