Imports System.Text.UnicodeEncoding
Dim str As String = "我要被加密了!"
"将字符串转换为 ascii 码数组
Dim strb1() As Byte = Unicode.GetBytes(str)
"加密转换后的字符串
Dim newstr As String = System.Convert.ToBase64String(strb1)
Label1.Text = "加密后是:" + newstr
"将加密后的字符串转换成 ascii 码数组
Dim strb2() As Byte = System.Convert.FromBase64String(newstr)
"解密转换后的字符串
Dim oldstr As String = Unicode.GetString(strb2)
Label1.Text += "<br><br>原来的字符串是:" + oldstr