replace one tag in content of one cell and format not changed

[replace one tag in content of one cell a]

I want to replace one tag '#abc#':
for example, the content of cell is: 123#abc#456
the format of '123' is Bold
the color of '456' is red
After replaced these formats of words don't be changed
How can I do?
VBScript?
Now if I use the function of replace, only one format is left

 

[Dave Peterson]

You have a reply at your other post.

I want to replace one tag '#abc#':
for example, the content of cell is: 123#abc#456
the format of '123' is Bold
the color of '456' is red
After replaced these formats of words don't be changed
How can I do?
VBScript?
Now if I use the function of replace, only one format is left