/// <summary>
/// Evaluates the specified JavaScript code within the scope of this
/// document. Returns the value computed by the last expression in the
/// code block after implicit conversion to a string.
/// </summary>
/// <example>
/// The following example shows an alert dialog then returns the string "4".
/// <code>
/// Eval("window.alert('Hello world!'); 2 + 2");
/// </code>
/// </example>
/// <param name="javaScriptCode">The JavaScript code</param>
/// <returns>The result converted to a string</returns>
/// <exception cref="JavaScriptException">Thrown when the JavaScript code cannot be evaluated
/// or throws an exception during evaluation</exception>
public virtual string Eval(string javaScriptCode)
{
var documentVariableName = NativeDocument.JavaScriptVariableName;
var resultVar = documentVariableName + "." + RESULT_PROPERTY_NAME;
var errorVar = documentVariableName + "." + ERROR_PROPERTY_NAME;
var exprWithAssignment = resultVar + " = '';" + errorVar + " = '';"
+ "try {"
+ resultVar + " = String(eval(" + JavascriptStringEncoder.Encode(javaScriptCode) + "))"
+ "} catch (error) {"
+ errorVar + " = 'message' in error ? error.name + ': ' + error.message : String(error)"
+ "};";
// Run the script.
RunScript(exprWithAssignment);
// See if an error occured.
var error = NativeDocument.GetPropertyValue(ERROR_PROPERTY_NAME);
if (!string.IsNullOrEmpty(error))
{
throw new JavaScriptException(error);
}
// Return the result
return(NativeDocument.GetPropertyValue(RESULT_PROPERTY_NAME));
}
/// <summary>
/// Evaluates the specified JavaScript code within the scope of this
/// document. Returns the value computed by the last expression in the
/// code block after implicit conversion to a string.
/// </summary>
/// <example>
/// The following example shows an alert dialog then returns the string "4".
/// <code>
/// Eval("window.alert('Hello world!'); 2 + 2");
/// </code>
/// </example>
/// <param name="javaScriptCode">The JavaScript code</param>
/// <returns>The result converted to a string</returns>
/// <exception cref="JavaScriptException">Thrown when the JavaScript code cannot be evaluated
/// or throws an exception during evaluation</exception>
public virtual string Eval(string javaScriptCode)
{
var documentVariableName = NativeDocument.JavaScriptVariableName;
var resultPropertyName = RESULT_PROPERTY_NAME + RandomString(10);
var errorPropertyName = ERROR_PROPERTY_NAME + RandomString(10);
var resultVar = documentVariableName + "." + resultPropertyName;
var errorVar = documentVariableName + "." + errorPropertyName;
var exprWithAssignment = resultVar + " = '';" + errorVar + " = '';"
+ "try {"
+ resultVar + " = String(eval('" + javaScriptCode.Replace("'", "\\'") + "'))"
+ "} catch (error) {"
+ errorVar + " = 'message' in error ? error.name + ': ' + error.message : String(error)"
+ "};";
// Run the script.
RunScript(exprWithAssignment);
var allElements = NativeDocument.AllElements; // forcing browser to refresh all elements
// See if an error occured.
var error = NativeDocument.GetPropertyValue(errorPropertyName);
if (!string.IsNullOrEmpty(error))
{
throw new JavaScriptException(error);
}
// Return the result
return(NativeDocument.GetPropertyValue(resultPropertyName));
}