Passing string included dollar signs to -Replace Variable

Question

I am trying to replace a sentence in .config file using powershell.

${c:Web.config} = ${c:Web.config} -replace

\'$BASE_PATH$\\

Answer 1

For those unfamiliar with the distinction, it is important not to confuse the backtick character (`) with the single-quotation character (') in these escapes. For example:

[SUCCESS] Double quotes as container with backslash-backtick as escape:

PS C:\Temp> 'What is $old?' | ForEach-Object {$_ -replace "\`$old", "(New)"}
What is (New)?
PS C:\Temp>

[FAIL] Double quotes as container with backslash-apostrophe as escape:

PS C:\Temp> 'What is $old?' | ForEach-Object {$_ -replace "\'$old", "(New)"}
What is $old?
PS C:\Temp>

[SUCCESS] Single quotes as container with simple backslash as escape:

PS C:\Temp> 'What is $old?' | ForEach-Object {$_ -replace '\$old', "(New)"}
What is (New)?
PS C:\Temp>

[FAIL] Single quotes as container with backslash-backtick as escape:

PS C:\Temp> 'What is $old?' | ForEach-Object {$_ -replace '\`$old', "(New)"}
What is $old?
PS C:\Temp>

Overall, the easiest option may be to use single quotes as the container and a single backslash as the escape: '\$old'