PhpStorm 2018.3 Help

Evaluating Expressions

With PhpStorm, you can evaluate arbitrary single-line expressions and quickly evaluate an expression in the editor at caret or a selection.

While using the Expression Evaluation feature, mind the following:

  • A method can be invoked within the Evaluate 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 PhpStorm stops at a breakpoint within a method called from the Expression Evaluation, you cannot use the Expression Evaluation feature again.

Evaluating expressions using the dedicated dialog

To evaluate arbitrary expressions

  1. Open the Evaluate Expression dialog box in one of the following ways:
    • Choose Run | Evaluate Expression on the main menu.

    • PressAlt+F8.

    • To evaluate a specific variable, select it on the Variables pane of the Debug tool window, then choose Run | Evaluate Expression or press Alt+F8.

  2. 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.

      If you have selected a specific variable on the Variables pane, this variable will be displayed in the Expression text box.

    • To evaluate a code fragment, click the Code Fragment Mode button and fill in the Code Fragment text box.

      To return to the original mode, click the Expression mode button.

  3. 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 icons general add expands the node and displays all children.

You can also use the Quick Evaluate expression functionality that lets you view the value of an expression using the keyboard only.

There are two ways to evaluate an expression quickly:

Show value tooltip on code selection

  1. In the Debugger | Data Views settings page, enable the Show value tooltip on code selection option.

  2. Select a code fragment with the mouse, or by pressing Ctrl+W. A tooltip with the expression value automatically appears under the selection and changes each time you change the selection.

    ps evaluate selection

Manually invoke the tooltip with the expression value

  1. Place the caret at the desired location, or select an expression to be evaluated.

  2. Choose Run | Quick Evaluate Expression on the main menu, or press Ctrl+Alt+F8. The tooltip with the expression value appears under the selected expression.

Evaluating variables in the console pane

In the PHP and JavaScript context, you can view the values of variables right in the Debug tool window during a debugging session. This can be done in several ways:

  • Select the variable in question in the Variables pane and choose Evaluate in Console on the context menu of the selection. When you switch to the Console pane, the variable name is shown in green at > and its value is displayed below in blue.

  • Alternatively you can type the name of any variable at > in the Console manually and press Enter to have its value displayed. Code completion is at your disposal: as you type the name of a variable, PhpStorm displays a suggestion list. Note that this functionality is available only when the Use Console Input toggle button is pressed.

  • To evaluate a previously evaluated variable without searching for it in the Variables pane, find the variable in question using the Up and Down arrows on you keyboard and press Enter.

Executing code in the console pane during a debugging session

During a PHP debugging session, you can not only evaluate variables, but also change their values, call PHP functions, and define additional ones right in the Console pane. Note that this functionality is not available for PHPUnit or Behat run/debug configurations.

  1. Start a debugging session (see PHP Debugging Session) and switch to the Console pane of the Debugger tab.

  2. Press the Use Console Input toggle button ps tool window debug console use input on the toolbar.

  3. Type a statement or expression at > and press Enter. PhpStorm evaluates your code fragment and shows the output below the input code. You can type most PHP constructs including class declarations, function declarations, variables, expressions, etc. Code completion is at your disposal: as you type, PhpStorm displays a suggestion list.

  4. When typing a multi-line code fragment, press Shift+Enter to start a new line and Ctrl+Enter to split a line.

  5. Output for arrays and objects is by default wrapped in a var_export() function and displayed in the Console. To hide the output displayed, clear the Show array and object children in Debug Console checkbox on the Debug page.

Last modified: 18 March 2019

See Also