System.FormatException : Input string was not in a correct format ,on converting string to decimal.

I have a little problem with ASP.NET and C#. This is my error code:

An exception of type ‘System.FormatException’ occurred in mscorlib.dll but was not handled in >user code

Additional information: Input string was not in a correct format.

protected void Page_Load(object sender, EventArgs e)
{
    if(this.IsPostBack == false)
    {
        Currency.Items.Add(new ListItem("Euro", "0.85"));
        Currency.Items.Add(new ListItem("Yen", "11.30"));
        Currency.Items.Add(new ListItem("PLN", "4.20"));
        Currency.Items.Add(new ListItem("GBP", "5.62"));
    }
}

protected void Convert_Click(object sender, EventArgs e)
{
    decimal oldAmount;
    bool succes = Decimal.TryParse(TextBox.Value, out oldAmount);

    if(succes)
    {
        ListItem item = Currency.Items[Currency.SelectedIndex];
        decimal newAmount = oldAmount * decimal.Parse(item.Value);
        Result.InnerText = "Result: " + newAmount;
    }

}

I tried Decimal.Parse, Decimal.TryParse and other strange combinations. Now I’m sure that issue is with strings and parsing them to decimal. When I created String variable – there was that same error while parsing. So can someone tell me what to do to be able to convert String to decimal?

Answers:

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Method 1

Try using “0,85” instead of “0.85”. I think you can use the dot decimal if you change culture.
Here is some more information:
How to change symbol for decimal point in double.ToString()?

Method 2

Please try with the below code snippet.

CultureInfo info = CultureInfo.GetCultureInfo("es-ES");
string storedValue = "3,85";
decimal oldAmount;
bool succes = Decimal.TryParse(storedValue, NumberStyles.Any, info, out oldAmount);

Method 3

Use TextBox.Text instead:

bool succes = Decimal.TryParse(TextBox.Text, out oldAmount);

Method 4

TextBox.value is wrong. YourTextBox.Text is correct…!

bool success = Decimal.TryParse(TextBox.Text, out oldAmount);

All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0