Upper case, Lower case, Proper Case or Title Case in C#

Convert a string to Uppercase

String Sub_Code = txtcode.Text.ToUpper();

Convert a string to Lowercase

String Sub_Code = txtcode.Text.ToLower();

Note : ToLower and ToUpper are methods of string class.

Convert a string to ProperCase or TitleCase

The String class does not include any method that converts a string to title case. To convert  a string to title case we use ToTitleCase method which resides in the TextInfo class, which is a member of the System.Globalization namespace. Unlike the ToUpper and ToLower methods of the String class, the ToTitleCase method is not a static method and requires an instance of the class.

When we use the TextInfo class, we must specify cultural information. CultureInfo class represents information about a specific culture including the names of the culture, the writing system, and the calendar used, as well as access to culture-specific objects that provide information for common operations, such as formatting dates and sorting strings.

Example :

CultureInfo cultureinfo = CultureInfo.InvariantCulture;

TextInfo textinfo = cultureinfo.TextInfo;

string Sub_Name =textinfo.ToTitleCase(txtname.Text);

 

Substring Function

For any function there arises three basic question--:

1. What does it mean?
2. Why is this?
3. How it works?

What does it mean?

As we see SubString is a combination of two words "Sub" and "String".
String-: In Computer Science String  means "A set of consecutive characters".
Sub   -: Sub is basically a Latin prefix which has several meaning but the best suitable meaning for here is "part of".
So, Substring means "Part of a string".

Why is this?

So, from definition its clear that the work of substring is to extract a part of string.

How it works? 

Syntax : Substring(index,length)
            Here index denotes the postion from where you want to extract the string and length denotes up to how much character you need to extract.Both contains integer value.
Example :
        int ind = Convert.ToInt32(txtIndex.Text);
        int len = Convert.ToInt32(txtLength.Text);
        Literal1.Text = TextBox1.Text.Substring(ind,len); 

You can download Sample Code from Here