Get specific string after specific character

Question

I have a few string:

1. <img title=\"\\angle X &lt; \\angle Y &lt; \\angle Z\" src=\"http://latex.codecogs.com/gif.latex?\\angle&amp;space;X&amp;space;&lt;&amp;space;\\angle&amp;space;Y&amp;space;&lt;&amp;space;\\angle&amp;space;Z\" />

I want to get angle&space;X&space;<&space;\\angle&space;Y&space;<&space;\\angle&space;Z

and

2. <img title=\"1,25 - \\frac{5}{6} \\times 280\\% \\div 1\\tfrac{1}{6}\" src=\"http://latex.codecogs.com/gif.latex?1,25&amp;space;-&amp;space;\\frac{5}{6}&amp;space;\\times&amp;space;280\\%&amp;space;\\div&amp;space;1\\tfrac{1}{6}\" />

I want to get:

frac{5}{6}&space;\\times&space;280\\%&space;\\div&space;1\\tfrac{1}{6}

Code:

string imgSoal;
string imgName = imgSoal.Split("\\")[1];

I'm having a problem, ie the string that I got from the above code are angle&space;X&space;<&space; and frac{5}{6}&space; How to get string i want ( angle&space;X&space;<&space;\\angle&space;Y&space;<&space;\\angle&space;Z and frac{5}{6}&space;\\times&space;280\\%&space;\\div&space;1\\tfrac{1}{6} )?

Answer 1

You can use the IndexOf method to get the first occurrence of the \\ (inputChar) and then get the remaining string by using the SubString method.

var result = str.Substring(str.IndexOf(inputChar) + 1);

You need the handle the case if the given character is not present in the given string.

Answer 2

For your requirement, the better way is create Regex to match the string that your want then remove unrelated character. I have implement the follow code please check.

private string stringA = "<img title=\"\\angle X &lt; \\angle Y &lt; \\angle Z\" src=\"http://latex.codecogs.com/gif.latex?\\angle&amp;space;X&amp;space;&lt;&amp;space;\\angle&amp;space;Y&amp;space;&lt;&amp;space;\\angle&amp;space;Z\" />";
private string stringB = "<img title=\"1,25 - \\frac{5}{6} \\times 280\\% \\div 1\\tfrac{1}{6}\" src=\"http://latex.codecogs.com/gif.latex?1,25&amp;space;-&amp;space;\\frac{5}{6}&amp;space;\\times&amp;space;280\\%&amp;space;\\div&amp;space;1\\tfrac{1}{6}\" />";
private string patternA = @"\?(.*?)/>";
private string patternB = @";\\frac(.*?)/>";

foreach (Match match in Regex.Matches(stringA, patternA))
{

    Console.WriteLine(match.Value);
    var tem = match.Value.Remove(0, 2);
    var res = tem.Substring(0, tem.Length - 4);
}
foreach (Match match in Regex.Matches(stringB, patternB))
{

    Console.WriteLine(match.Value);
    var tem = match.Value.Remove(0, 2);
    var res = tem.Substring(0, tem.Length - 4);
}