C#如何实现 ASCII码与字母的互相转换？

字母转换成ASCII码方法

 private void button1_Click(object sender, EventArgs e)
         {            
         if (textBox1.Text != "")            
         {                
         if(Encoding.GetEncoding("unicode").GetBytes(new char[] { textBox1.Text[0] })[1] == 0)                
         {                    
         textBox2.Text = Encoding.GetEncoding("unicode").GetBytes(textBox1.Text)[0].ToString();                
         }                
         else                
         {                    
         textBox2.Text = "请输入字母！";                
         }            
         }        
         }

ASCII码转换成字母方法

 private void button2_Click(object sender, EventArgs e)        
 {            
 if (textBox3.Text != "")            
 {                
 int a;                
 if(int.TryParse(textBox3.Text,out a))                
 {                    
 textBox4.Text = ((char)a).ToString();                
 }                
 else                
 {                    
 textBox4.Text = "请输入正确的ASCII码";                
 }            
 }        
 }