Question

I am working on asp.net based application. I am using multi-line textbox and I am using java script in asp.net.I want to find a line number of a particular character or text in a multi-line textbox. How can I get line number from a multi-line textbox using Javascript?

Answer 1

string[] lines = Textbox1.Text.Split(new string[] { Environment.NewLine }, StringSplitOptions.None);
int lineNumberOfText = -1;
for (int lineNumber = 0; lineNumber <= lines.Length - 1; lineNumber++) {
    if (lines(lineNumber).Contains(textToSearch)) {
        lineNumberOfText = lineNumber;
        break; 
    }
}

Edit: You just changed the title from ASP.NET to javascript, so this answer is incorrect but might be helpful anyhow.

Here’s a Javascript function that does what you want(with the option of case-insitive search):

function getLineNumber(id, text, caseSensitive) {
    var input = document.getElementById(id);
    if (input != null) {
        caseSensitive = (caseSensitive == true || caseSensitive == "true") ? true : false;
        if (!caseSensitive) text = text.toLowerCase();
        var lines = input.value.split('\n');
        for (var i = 0; i < lines.length; i++) {
            var line = caseSensitive ? lines[i] : lines[i].toLowerCase();
            if (line.indexOf(text) != -1) {
                return i;
            }
        }
    }
    return -1;
}