How to change text and numbers in a code

I hope you guys can help me out a little.

I have 2 codes here that i want unique numbers and texts in it (The numbers and the texts that i have highlighted with fater text) to be random every time i klick button1 in visual studio, the whole sentence will then show up with the random texts and numbers in Textbox1

1: True&createdAt=2015-05-04%2012%3A36%3A44&start.game=2H7QTB&steece=true&maskedgamestars=889980**********102&end=6

2: 1975259&begin=329518&keep.mess=2H7QTB&check=v044395deb83b724d2a0233daf27b72ca5b&=&

I hope you guys can help me here:) Thanks!