Get chrome's console log

I don't know C# but here's Java code that does the job, I hope you can translate it to C#

import org.openqa.selenium.WebDriver;
import org.openqa.selenium.chrome.ChromeDriver;
import org.openqa.selenium.logging.LogEntries;
import org.openqa.selenium.logging.LogEntry;
import org.openqa.selenium.logging.LogType;
import org.openqa.selenium.logging.LoggingPreferences;
import org.openqa.selenium.remote.CapabilityType;
import org.openqa.selenium.remote.DesiredCapabilities;
import org.testng.annotations.AfterMethod;
import org.testng.annotations.BeforeMethod;
import org.testng.annotations.Test;

public class ChromeConsoleLogging {
    private WebDriver driver;


    @BeforeMethod
    public void setUp() {
        System.setProperty("webdriver.chrome.driver", "c:\\path\\to\\chromedriver.exe");        
        DesiredCapabilities caps = DesiredCapabilities.chrome();
        LoggingPreferences logPrefs = new LoggingPreferences();
        logPrefs.enable(LogType.BROWSER, Level.ALL);
        caps.setCapability(CapabilityType.LOGGING_PREFS, logPrefs);
        driver = new ChromeDriver(caps);
    }

    @AfterMethod
    public void tearDown() {
        driver.quit();
    }

    public void analyzeLog() {
        LogEntries logEntries = driver.manage().logs().get(LogType.BROWSER);
        for (LogEntry entry : logEntries) {
            System.out.println(new Date(entry.getTimestamp()) + " " + entry.getLevel() + " " + entry.getMessage());
            //do something useful with the data
        }
    }

    @Test
    public void testMethod() {
        driver.get("http://mypage.com");
        //do something on page
        analyzeLog();
    }
}

Pay attention to setUp method in above code. We use LoggingPreferences object to enable logging. There are a few types of logs, but if you want to track console errors then LogType.BROWSER is the one that you should use. Then we pass that object to DesiredCapabilities and further to ChromeDriver constructor and voila - we have an instance of ChromeDriver with logging enabled.

After performing some actions on page we call analyzeLog() method. Here we simply extract the log and iterate through its entries. Here you can put assertions or do any other reporting you want.

My inspiration was this code by Michael Klepikov that explains how to extract performance logs from ChromeDriver.

You can get logs this way:

Driver().Manage().Logs.GetLog();

By specifying what log you are interested in you can get the browser log, that is:

Driver().Manage().Logs.GetLog(LogType.Browser);

Also remember to setup your driver accordingly:

ChromeOptions options = new ChromeOptions();
options.SetLoggingPreference(LogType.Browser, LogLevel.All);
driver = new ChromeDriver("path to driver", options);

This is the c# code for logging the brower log from chrome.

private void CheckLogs()
    {
        List<LogEntry> logs = Driver.Manage().Logs.GetLog(LogType.Browser).ToList();
        foreach (LogEntry log in logs)
        {
            Log(log.Message);
        }
    }

here is my code for the actual log:

        public void Log(string value, params object[] values)
    {
        // allow indenting
        if (!String.IsNullOrEmpty(value) && value.Length > 0 && value.Substring(0, 1) != "*")
        {
            value = "      " + value;
        }

        // write the log
        Console.WriteLine(String.Format(value, values));
    }

As per issue 6832 logging is not implemented yet for C# bindings. So there might not be an easy way to get this working as of now.