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.
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
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";
}
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.
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
Use some sort of eval
if it is available in the language.
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.
来源:https://stackoverflow.com/questions/1147967/how-to-create-variables-with-dynamic-names-in-c