Get this error when I try to debug. "An exception of type 'System.OutOfMemoryException' occurred in mscorlib.dll but was not handled in user code"

I am trying to make a application that makes all the first letters to capital letters and the others to small. 

string navn = txtNavn.Text;
string delnavn1, delnavn2;

delnavn1 = navn.Substring(0, 1).ToUpper();
delnavn2 = navn.Substring(1).ToLower();
navn = delnavn1 + delnavn2;

if (navn.Contains(" "))
{

    for (int i = 0; i < navn.Length; i++)
    {
        if (navn.Substring(i, 1) == " ")
        {
            delnavn1 = navn.Substring(i, 1).ToUpper();
            delnavn2 = navn.Substring(i + 2).ToLower();
            navn += delnavn1 + delnavn2 + " ";
        }

    }

}
else
{
    delnavn1 = navn.Substring(0, 1).ToUpper();
    delnavn2 = navn.Substring(1).ToLower();
    navn = delnavn1 + delnavn2;
}


txbMelding.Text = "Du heter " + navn;

Sorry for weird variablenames, I am norwegian and did not have enough time to change them.

Jon Skeet
people
quotationmark

I suspect this is the immediate problem:

navn += delnavn1 + delnavn2 + " ";

You're concatenating with the previous value of navn. So if you start off with "Hello there", when you get to the first space you'll have:

delnavn1 = " "
delnavn2 = "There"
navn = "Hello there" + delnavn1 + delnavn2;

i.e. navn = "Hello there There".

Here's a rather simpler approach:

char[] text = txtNavn.Text.ToCharArray();
for (int i = 0; i < text.Length; i++)
{
    char c = text[i];
    text[i] = i == 0 || text[i - 1] == ' '
        ? char.ToUpper(c)
        : char.ToLower(c);       
}
txbMelding.Text = "Du heter " + new string(text);

Replacing the letters in an array "in place" is much simpler than messing around with strings concatenation and substrings.

Note that this is still a very crude way of performing title-casing - you should probably look at TextInfo.ToTitleCase for a more comprehensive culture-sensitive code (and code that you don't need to write yourself!)

people

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