Resilient Automation

SAP GUI is timing-sensitive. Network latency, slow ABAP reports, and post-navigation busy pulses all cause flaky automation when you interact with the screen too early. The wrapper provides five methods to handle this:

Method	Use when
WaitReady(timeoutMs)	Simple busy-flag poll after navigation
WaitForReadyState(timeoutMs, pollMs, settleMs)	Stricter: also waits for a settle period and verifies the main window is reachable
ElementExists(id, timeoutMs)	Poll until a specific component appears before touching it
WaitUntilHidden(id, timeoutMs)	Poll until a loading spinner or progress dialog disappears
WithRetry(maxAttempts, delayMs).Run(…)	Re-execute a block on SapComponentNotFoundException or TimeoutException

WaitReady — simple busy-flag poll

session.PressExecute();
session.WaitReady(timeoutMs: 30_000); // default: 30 s, polls every 200 ms

Use this after short navigation steps. For screen transitions that involve a brief second busy pulse, prefer WaitForReadyState.

WaitForReadyState — stricter wait

After screen transitions:

session.StartTransaction("/nMM60");
// Waits until IsBusy is false, adds a 300 ms settle, then confirms the main window is reachable.
session.WaitForReadyState(timeoutMs: 15_000, settleMs: 300);

Default values: timeoutMs = 30_000, pollMs = 200, settleMs = 0.

ElementExists — wait for a component to appear

Don't call typed finders until the field is actually on screen:

const string reportField = "wnd[0]/usr/ctxtSELWERKS-LOW";

if (!session.ElementExists(reportField, timeoutMs: 8_000))
    throw new Exception("Selection screen did not load in time.");

session.TextField(reportField).Text = plant;

WaitUntilHidden — wait for a spinner or dialog to close

const string spinner = "wnd[1]/usr/txtMESSAGE";
session.PressExecute();
session.WaitUntilHidden(spinner, timeoutMs: 60_000);
session.WaitForReadyState(timeoutMs: 10_000);

WithRetry — resilient execution block

WithRetry retries on SapComponentNotFoundException (slow screen loads) and TimeoutException (session still busy). It never retries on SapGuiNotFoundException — that is a fatal setup error and should propagate immediately.

session.WithRetry(maxAttempts: 3, delayMs: 500).Run(() =>
{
    session.StartTransaction("/nMM60");
    session.WaitForReadyState(timeoutMs: 15_000);
    session.TextField("wnd[0]/usr/ctxtSELWERKS-LOW").Text = plant;
    session.PressExecute();
    session.WaitForReadyState(timeoutMs: 30_000);
});

Return a value from the protected block with Run<T>:

string status = session.WithRetry(maxAttempts: 3, delayMs: 400).Run(() =>
{
    session.WaitReady(timeoutMs: 10_000);
    return session.Statusbar().Text;
});

Combined pattern — navigate, wait, read

using var sap     = SapGuiClient.Attach();
var       session = sap.Session;

const string tableField = "wnd[0]/usr/ctxtDATABROWSE-TABLENAME";

// 1. Navigate with retry in case the first attempt races
session.WithRetry(maxAttempts: 3, delayMs: 400).Run(() =>
{
    session.StartTransaction("/nSE16");
    session.WaitForReadyState(timeoutMs: 10_000);
    if (!session.ElementExists(tableField, timeoutMs: 5_000))
        throw new SapComponentNotFoundException(tableField);
});

// 2. Interact only after the page is confirmed ready
session.TextField(tableField).Text = "MARA";
session.PressExecute();
session.WaitForReadyState(timeoutMs: 30_000);

// 3. Wait for a progress dialog to disappear
bool hadSpinner = session.WaitUntilHidden("wnd[1]", timeoutMs: 60_000);
if (hadSpinner) Log("Progress dialog closed.");

var grid = session.GridView("wnd[0]/usr/cntlGRID/shellcont/shell");
Log($"Rows returned: {grid.RowCount}");

Exception types reference

Exception	When thrown
SapGuiNotFoundException	SAP GUI not running or scripting disabled — fatal, never retried
SapComponentNotFoundException	FindById path not found — retried by WithRetry
TimeoutException	WaitReady timed out while session was busy — retried by WithRetry
InvalidCastException	FindById<T> found a component of the wrong type
InvalidOperationException	LaunchWithSso session conflict or connection error