ToUpper and ToLower first char and first word

Question

Hello,

Going to convert the first letter of each word to upper and lower case, to upper is simple, but to lower?

System.Globalization.CultureInfo.CurrentCulture.TextInfo.ToTitleCase(---)

And to convert the first word of string to upper and lower case, no methods in .net?

Thanks.

Answer 1

Hi @StewartBW ,

You can write one yourself, referring to the function below.

    Function ConvertToFirstLetterLowerCase(input As String) As String
        If String.IsNullOrWhiteSpace(input) Then
            Return input
        End If

        Dim words As String() = input.Split(" "c)

        For i As Integer = 0 To words.Length - 1
            If words(i).Length > 0 Then
                words(i) = Char.ToLower(words(i)(0)) & words(i).Substring(1)
            End If
        Next

        Return String.Join(" ", words)
    End Function

Best Regards.

Jiachen Li

---

If the answer is helpful, please click "Accept Answer" and upvote it.

Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.

Answer 2

The following extension method lower cases the first character to lower.

public static class StringExtensions
{
    public static string? FirstCharToLowerCase(this string? sender)
    {
        if (!string.IsNullOrEmpty(sender) && char.IsUpper(sender[0]))
            return sender.Length == 1 ? 
                char.ToLower(sender[0]).ToString() : 
                char.ToLower(sender[0]) + sender[1..];

        return sender;
    }
}