How to check a List for values

Hakan Axheim

Hi,

I have a List values = new List();

values.add("0");This

values.add("1");

values.add("9)";

Only values 0 and 9 are valid so therefore I must check if the list above has values that are different from the values 0 and 9. I need help with that from someone that is experienced in C#.

I have tried with this;

This if statement will always be true because I only check for 0 and 9.

if (values.ContainshT("0") && values.Contains("9"))

This if statement will also be true because there is an item that is different from 0 and 9.

if (!values.ContainshT("0") && !values.Contains("9"))

How to check if items exist other than 0 and 9 it is false and if only items 0 and 9 exist then it is true.

3 Replies

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Nitin Sontakke5y ago
Accepted answer
Hello,

Here is a piece of code you can try.

This cannot be achieved by a single if statement. You will need to check EACH element of an list.
private void button2_Click(object sender, EventArgs e)
{
    List validValues = new List();
    validValues.Add("0");
    validValues.Add("9");

    List values1 = new List();
    values1.Add("9");
    values1.Add("3");
    values1.Add("0");
    values1.Add("9");
    values1.Add("4");
    values1.Add("1");
    values1.Add("9");
    values1.Add("6");
    values1.Add("1");

    List values2 = new List();
    values2.Add("9");
    values2.Add("0");
    values2.Add("9");
    values2.Add("0");
    values2.Add("9");
    values2.Add("0");
    values2.Add("9");
    values2.Add("0");
    values2.Add("9");

    Boolean result1 = validValuesOnly(validValues, values1);    // returns False
    Boolean result2 = validValuesOnly(validValues, values2);    // returns True
}

private Boolean validValuesOnly(List validValues, List values)
{
    foreach (String value in values)
    {
        if (!validValues.Contains(value))
            return false;
    }
    return true;
}
Hope it helps!
Sachin Singh5y ago
if i am not wrong this can be achieved with a single If
if(strList.Any(x=>!(x=="0" || x=="9" ))
{
   // do processing
}
Sachin Singh5y ago
you were almost there , just a little modification required
bool isValid= strList.Any(x=>!(x=="0" || x=="9" );