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In addition to regular expressions, you can also evaluate operator expressions, lambda expressions, and anonymous classes.
The following evaluation modes are available:
- A method can be invoked within the Expression Evaluation dialog only if the debugger has stopped at a breakpoint, but has not been paused.
- Expression Evaluation can only be "single-level". In other words, if Rider stops at a breakpoint within a method called from the Expression Evaluation, you cannot use the Expression Evaluation feature again.
Evaluating arbitrary expressions
- Open the Evaluate Expression dialog box in one of the following ways:
- In the Evaluate Expression dialog box, specify the expression you want to evaluate. Do one of the following:
- In the Expression field, type the expression in question or choose one of the previously evaluated expressions from the drop-down list.
- To evaluate a code fragment, click the Code Fragment Mode button and fill in the Code Fragment text box.
- Click the Evaluate button. The Result read-only field shows the evaluation output. If the specified expression cannot be evaluated, the Result field explains the reason.
Evaluating expressions in the editor
During a debugger session, the value of any expression is shown in the tooltip every time you hover your mouse pointer over it. If an expression contains children, clicking expands the node and displays all children.
There are two ways to evaluate an expression quickly:
- By using the Show value tooltip on code selection functionality:
- In the Debugger | Data Views settings page, enable the Show value tooltip on code selection option.
- Select a code fragment with the mouse, or by pressing Ctrl+Alt+Right. A tooltip with the expression value automatically appears under the selection and changes each time you change the selection.
- By manually invoking the tooltip with the expression value: