将.txt文件解析为不同的数据类型

Question

So I have a text file that reads as the following

-9
5.23
b
99
Magic
1.333
aa

When I try to read it in using the following code, the GetType() function outputs it as strings:

string stringData;

streamReader = new StreamReader(potato.txt);
while (streamReader.Peek() > 0)
{
    data = streamReader.ReadLine();
    Console.WriteLine("{0,8} {1,15}", stringData, stringData.GetType());
}

Here then is the output:

-9      System.String
5.23    System.String
b       System.String
99      System.String
Magic   System.String
1.333   System.String
aa      System.String

I understand that I asked the streamReader class to read it all in as strings.

My question is, how does one read it as the different different data types (ie string, int, double), and have it output as:

-9      System.int
5.23    System.double
b       System.String
99      System.int
Magic   System.String
1.333   System.double
aa      System.String

Answer 1

You have to convert string to that types:

string stringData;
double d;
int i;

streamReader = new StreamReader(potato.txt);
while (streamReader.Peek() > 0)
{
   data = streamReader.ReadLine();

   if (int.TryParse(data, out i) 
   {       
       Console.WriteLine("{0,8} {1,15}", i, i.GetType());
   }
   else if (double.TryParse(data, out d) 
   {       
       Console.WriteLine("{0,8} {1,15}", d, d.GetType());
   }
   else Console.WriteLine("{0,8} {1,15}", data, data.GetType());
}

Answer 2

Normally you would know the types (the structure of the file).

If not, use RegEx to check for possible int and double values, return the rest as string .