Check out example codes for "using in c#". It will help you in understanding the concepts better.

Code Example 1

//doing with using function
using (var font1 = new Font("Arial", 10.0f)) 
{
    byte charset = font1.GdiCharSet;
}

//or
using var font1 = new Font("Arial", 10.0f);
byte charset = font1.GdiCharSet;

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