正则表达式从字符串中检索文本

Question

I have a string which will have values like

{ctrl1} + {ctrl2}
({ctrl1} / {ctrl2}) * {ctrl3}
if ({ctrl1} > {ctrl2}) then {ctrl1} * 10 else {ctrl} + {ctrl2} endif

there could be several formulas like this. This will be available in a string variable. I need extract all {..} values.

So, in example1, I should extract {ctrl1} , {ctrl2} . In Example2, I should extract {ctrl1} , {ctrl2} , {ctrl3} . In example3, I should extract {ctrl1} , {ctrl2} .

Can someone please help me with a regex for this?

Answer 1

You probably want something like {[^}]+} .

Note however that that won't handle recursive stuff like {hello{2}} . You'll probably need an actual parser for things like that.

Answer 2

像{\\S+?}这样的东西应该可以解决问题。

Answer 3

You can combine regex and LINQ and do this:

Regex.Matches(input, "{.*?}").Cast<Match>().Select(m => m.Value).Distinct();

Assuming {ctrl} was a typo in the last example.

Answer 4

private void TrimControlNames()
    {
        if (txtFormula.Text.Trim().Length > 0)
        {
            string formula = txtFormula.Text.Trim();

            string pattern1 = "{[a-zA-Z0-9$_ ]+}"; //to identify control placeholders
            StringBuilder names = new StringBuilder();
            foreach (Match m in Regex.Matches(formula, pattern1))
            {
                if (m.Value.Contains(" "))
                {
                    string str = m.Value.Replace(" ", string.Empty); //It is ok to remove like this since control names are not allowed to have spaces.
                    formula = formula.Replace(m.Value, str);
                }

            }

            txtFormula.Text = formula;
        }

    }

This method performs what I expected.