Listbox not showing values in format I required

Hi,

I am binding values to list box but stirng not showing in proper format.

ex my strings like

abc               10
abcd              20
asdfas            30

I made fixed length to first string that is 30 using pading

str1.PadRight(30) + str2.PadRight(2)

then also I am getting values like that

abc     10
abcd        20
asdfas            30

Plese suggest how can I put same space between string