Cannot combine strings when they contain '{}' chars

Question

I am attempting to perform String Interpolation in C#. The input string I am attempting to combine contains many '{}' characters(because its javascript) which seems to be causing an error.

Why cant I perform string interpolation on these strings in C#?

string test = string.Format("{img: \"{0}\", html: \"{1}\"}", "images/a.png", "<div></div>");
// so the output should be
// "{img: \"images/a.png\", html: \"<div></div>\"}"

The error I get is:

Input string was not in a correct format.

Can you tell me how I can acheive my string interpolation?

How is `string.Format` supposed to tell the difference between `{img:` and `{0` ? — Ben Voigt, Feb 19 '12 at 23:55

score 5 · Accepted Answer · answered Feb 19 '12 at 23:56

5

Braces need to be escaped:

string test = string.Format("{{img: \"{0}\", html: \"{1}\"}}", "images/a.png", "<div></div>");

answered Feb 19 '12 at 23:56

usr

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score 1 · Answer 2 · answered Feb 19 '12 at 23:56

1

Braces have special meaning to string.Format, so you need to escape them.

See: http://msdn.microsoft.com/en-us/library/txafckwd.aspx

There's no simple way to do what you want, but that documentation page suggests some workarounds.

answered Feb 19 '12 at 23:56

Ben Voigt

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Cannot combine strings when they contain '{}' chars

2 Answers2