![]() ![]() 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 You must use the else clause on the same line as the command after the if. If there is, you'll get that CMDEXTVERSION value instead. This assumes that there isn't already an existing environment variable with the name CMDEXTVERSION. ![]() %cmdextversion%: Expands into the string representation of the current value of cmdextversion. If there is, you'll get that CMDCMDLINE value instead. This assumes that there isn't already an existing environment variable with the name CMDCMDLINE. %cmdcmdline%: Expands into the original command line that was passed to Cmd.exe prior to any processing by Cmd.exe. If there is, you'll get that ERRORLEVEL value instead. This variable assumes that there isn't already an existing environment variable with the name ERRORLEVEL. %errorlevel%: Expands into a string representation of the current value of the ERRORLEVEL environment variable. If you use defined, the following three variables are added to the environment: %errorlevel%, %cmdcmdline%, and %cmdextversion%. To use exit codes as conditions, use the errorlevel parameter. When a program stops, it returns an exit code. If the condition is false, the command in the if clause is ignored and the command executes any command that is specified in the else clause. If the condition specified in an if clause is true, the command that follows the condition is carried out. Specifies a command-line command and any parameters to be passed to the command in an else clause. Specifies a true condition if variable is defined. The cmdextversion conditional is never true when command extensions are disabled (by default, command extensions are enabled). It increases by increments of one when significant enhancements are added to the command extensions. 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 the number specified. These comparisons are generic, in that if both string1 and string2 are comprised of numeric digits only, the strings are converted to numbers and a numeric comparison is performed. You can use /i on the string1=string2 form of if. Specifies a three-letter comparison operator, including:įorces string comparisons to ignore case. Specifies a true condition if the specified file name exists. You do not need to enclose literal strings in quotation marks. These values can be literal strings or batch variables (for example, %1). Specifies a true condition only if string1 and string2 are the same. Specifies the command that should be carried out if the preceding condition is met. Specifies a true condition only if the previous program run by Cmd.exe returned an exit code equal to or greater than number. Specifies that the command should be carried out only if the condition is false. If command extensions are enabled, use the following syntax: if Performs conditional processing in batch programs.
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