If

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Performs conditional processing in batch programs.

Syntax

if [not] errorlevel Number Command [else Expression]

if [not] String1==String2 Command [else Expression]

if [not] exist FileName Command [else Expression]

If command extensions are enabled, use the following syntax:

if [/i] String1 CompareOp String2 Command [else Expression]

ifcmdextversionNumberCommand [else Expression]

ifdefinedVariableCommand [else Expression]

Parameters

not

Specifies that the command should be carried out only if the condition is false.

errorlevelNumber

Specifies a true condition only if the previous program run by Cmd.exe returned an exit code equal to or greater than Number.

Command

Specifies the command that should be carried out if the preceding condition is met.

String1==String2

Specifies a true condition only if String1 and String2 are the same. These values can be literal strings or batch variables (for example, %1). You do not need to use quotation marks around literal strings.

existFileName

Specifies a true condition if FileName exists.

CompareOp

Specifies a three-letter comparison operator. The following table lists valid values for CompareOp. OperatorDescriptionEQUequal toNEQnot equal toLSSless thanLEQless than or equal toGTRgreater thanGEQgreater than or equal to

Forces string comparisons to ignore case. You can use /i on the String1==String2 form of if. These comparisons are generic, in that if both String1 and String2 are both comprised of all numeric digits, the strings are converted to numbers and a numeric comparison is performed.

cmdextversionNumber

Specifies a true condition only if the internal version number associated with the Command Extensions feature of Cmd.exe is equal to or greater than Number. The first version is 1. It is incremented by one when significant enhancements are added to the command extensions. The cmdextversion conditional is never true when command extensions are disabled (by default, command extensions are enabled).

definedVariable

Specifies a true condition if Variable is defined.

Expression

Specifies a command-line command and any parameters to be passed to the command in an else clause.

Displays help at the command prompt.

Remarks

If the condition specified in an if command is true, the command that follows the condition is carried out. If the condition is false, the command in the if clause is ignored and the command executes any command in the else clause (that is, if you specify a command in the else clause).
When a program stops, it returns an exit code. To use exit codes as conditions, use errorlevel.
Using definedVariable

If you use definedVariable, the following three variables are added: %errorlevel%, %cmdcmdline%, and %cmdextversion%.

%errorlevel% expands into a string representation of the current value of errorlevel, provided that there is not an existing environment variable with the name ERRORLEVEL, in which case you get the ERRORLEVEL value instead. The following example illustrates how you can use errorlevel after running a batch program:
goto answer%errorlevel% :answer0 echo Program had return code 0 :answer1 echo Program had return code 1 goto end :end echo done!
You can also use the CompareOp comparison operators as follows:
```
if %errorlevel% LEQ 1 goto okay
```
%cmdcmdline% expands into the original command line passed to Cmd.exe prior to any processing by Cmd.exe, provided that there is not an existing environment variable with the name CMDCMDLINE, in which case you get the CMDCMDLINE value instead.

%cmdextversion% expands into the a string representation of the current value of cmdextversion, provided that there is not an existing environment variable with the name CMDEXTVERSION, in which case you get the CMDEXTVERSION value instead.
Using the else clause

You must use the else clause on the same line as the command after the if. For example:
IF EXIST FileName. ( del FileName. ) ELSE ( echo FileName. missing. )
The following code does not work because you must terminate the del command by a new line:
```
IF EXIST FileName. del FileName. ELSE echo FileName. missing
```
The following code does not work because you must use the else clause on the same line as the end of the if command:
IF EXIST FileName. del FileName. ELSE echo FileName. missing
If you want to format it all on a single line, use the following form of the original statement:
```
IF EXIST FileName. (del FileName.) ELSE echo FileName. missing
```

Examples

To display the message "Cannot find data file" if the file Product.dat cannot be found, type:

if not exist product.dat echo Cannot find data file

If an error occurs during the formatting of the disk in drive A, the following example displays an error message:

:begin
@echo off
format a: /s
if not errorlevel 1 goto end
echo An error occurred during formatting.
:end
echo End of batch program.

If no error occurs, the error message does not appear.

Formatting legend

Format	Meaning
Italic	Information that the user must supply
Bold	Elements that the user must type exactly as shown
Ellipsis (...)	Parameter that can be repeated several times in a command line
Between brackets ([])	Optional items
Between braces ({}); choices separated by pipe (\|). Example: {even\|odd}	Set of choices from which the user must choose only one
Courier font	Code or program output