I have a string builder and a list of object ,
int[] values = new int[] {1,2};
StringBuilder builder = new StringBuilder();
builder.AppendFormat("{0}, {1}", values );
I see an IntelliSense error
None existing arguments in format string
why am I seeing this error ,and how should I
I use a list parameters inside the AppendFormat
The overload of AppendFormat that you are currently using (or that the compiler decided to use) has the following signature:
public StringBuilder AppendFormat(string format, object arg0)
It is expecting a single argument and therefore a format that contains two arguments ("{0}, {1}") is invalid.
Your intention is to pass the array as multiple arguments, the overload that you need to use is the following:
public StringBuilder AppendFormat(string format, params object[] args)
Note that the second argument is an object[], not int[]. To make your code use this overload, you need to convert the int array into an object array like this:
builder.AppendFormat("{0}, {1}", values.Cast<object>().ToArray());
You need to pass in an object array instead of an int array. Otherwise it thinks the array object is the parameter for arg0.
object[] values = new object[] { 1, 2 };
StringBuilder builder = new StringBuilder();
builder.AppendFormat("{0}, {1}", values);
You need to loop through the list using foreach
int[] values = new int[] {1,2};
StringBuilder builder = new StringBuilder();
foreach (int val in values)
{
builder.AppendFormat("{0}\n", val);
}
Console.WriteLine(builder);
See the Working Fiddle.
In your case, you used:
builder.AppendFormat("{0}, {1}", values );
as you are passing 2 arguments {0}, {1} which is invalid for a single value of values as the outcome.
