Javascript 将正则表达式 \\\\n 替换为 \\n，\\\\t 替换为 \\t，\\\\r 替换为 \\r 等等

Question

I'm having an HTML Input field where the user can enter a delimiter.

This delimiter can include \\n, \\t, \\r and so on. When I append the delimiter to a string in javascript it is appended as \\n instead of as a newline character.

While I can use str.replace(/\\\\n/g, "\\n") and so on to replace one variation it does not work if I write a general catch-all regexp like str.replace(/\\\\([az])/g, "\\$1") since this just replaces \\n with \\n again.

How do I have to rewrite the RegExp to replace all double backslashes in front of a character?

Answer 1

There is no shortcut to replace literals with escaped sequences but you may be able to use this:

 const cmap = {'n': '\\n', 't': '\\t', 'r': '\\r'} var str = `value1\\rvalue2\\tvalue3\\nvalue4` str = str.replace(/\\\\([nrt])/g, m => {return cmap[m[1]]}) console.log(str)