how to 1 patterntText to replaced with Regex.Replace

Question

string inputText="lorem impsum dolar sit amet lorem";
string patternText="lorem";
string replacementText="XXXX";
Regex.Replace(inputText, patternText, replacementText, RegexOptions.IgnoreCase);

output:XXXX impsum dolar sit amet XXXX

But how do I make only one change ?

should be such that : XXXX impsum dolar sit amet lorem

Answer 1

I think you can use the overload of Regex. Replace to specify the maximum number of times to replace.

var regex = new Regex(Regex.Escape("o"));
var newText = regex.Replace("hi", "Foo", 1);