How to create variables with dynamic names in C#?

问题:

I want to create a var in a for loop, e.g.

for(int i; i<=10;i++)
{
    string s+i = "abc";
}

This should create variables s0, s1, s2... to s10.

回答1:

You probably want to use an array. I don't know exactly how they work in c# (I'm a Java man), but something like this should do it:

string[] s = new string[10];
for (int i; i< 10; i++)
{
    s[i] = "abc";
}

And read http://msdn.microsoft.com/en-us/library/aa288453(VS.71).aspx

回答2:

Your first example wouldn't work in any language as you are trying to redefine the variable "i". It's an int in the loop control, but a string in the body of the loop.

Based on your updated question the easiest solution is to use an array (in C#):

string[] s = new string[10];
for (int i; i< 10; i++)
{
    s[i] = "abc";
}

回答3:

Obviously, this is highly dependent on the language. In most languages, it's flat-out impossible. In Javascript, in a browser, the following works:

for (var i = 0; i<10 ; i++) { window["sq"+i] = i * i; }

Now the variable sq3, for example, is set to 9.

回答4:

You may use dictionary. Key - dynamic name of object Value - object

        Dictionary<String, Object> dictionary = new Dictionary<String, Object>();
        for (int i = 0; i <= 10; i++)
        {
            //create name
            string name = String.Format("s{0}", i);
            //check name
            if (dictionary.ContainsKey(name))
            {
                dictionary[name] = i.ToString();
            }
            else
            {
                dictionary.Add(name, i.ToString());
            }
        }
        //Simple test
        foreach (KeyValuePair<String, Object> kvp in dictionary)
        {
            Console.WriteLine(String.Format("Key: {0} - Value: {1}", kvp.Key, kvp.Value));
        }

Output:

Key: s0 - Value: 0
Key: s1 - Value: 1
Key: s2 - Value: 2
Key: s3 - Value: 3 
Key: s4 - Value: 4
Key: s5 - Value: 5
Key: s6 - Value: 6
Key: s7 - Value: 7
Key: s8 - Value: 8
Key: s9 - Value: 9
Key: s10 - Value: 10

回答5:

Use some sort of eval if it is available in the language.

回答6:

This depends on the language.

Commonly when people want to do this, the correct thing is to use a data structure such as a hash table / dictionary / map that stores key names and associated values.