'Failed to cast object' System.String [] 'to type' System.IConvertible '.&#-CodePudding

I need to read the numbers in the txt file in listBox and convert it to numbers. But I get an error ---> 'Failed to cast object' System.String [] 'to type' System.IConvertible '.' what can I do? I am using C # windows application. Thanks.

var lines = File.ReadAllLines("C:\\Numbers\\numbers.txt");

        for (int i = 0; i < lines.Length; i  )
        {
            var fields = lines[i].Split(' ');
            Convert.ToInt32(fields);
            listBox1.Items.Add(fields);
        }

CodePudding user response：

Split() gives you an array. You can't convert a whole array into numbers. Use a loop to iterate through the fields and add them to the listbox.

Also, you need to use the return value of Convert.ToInt32() (actually, when you assign it to a listbox, it will be converted to a string again).

CodePudding user response：

you don't need to convert string to int in order to add it to listbox items and you doing it wrong way. Just remove this line from your code

 Convert.ToInt32(fields);

and your code should be

List<string> items= new List<string>();
for (int i = 0; i < lines.Length; i  )
{
 var fields = lines[i].Split(' ');
 items.AddRange(fields);
}
ListBox1.Items.AddRange(items);