它可以編寫一個批處理純正的解決方案,而是寫一個強大的解決方案,可以處理任何你扔它是相當棘手,而最終的結果將是緩慢的。
這是很容易做到使用JScript和正則表達式的任務,但不是每個人都知道這些技術(雖然有可能更多的是知道JScript和正則表達式比知道批!)
我寫了一個混合的JScript /批處理實用程序,稱爲REPL.BAT,可以通過命令行或批處理文件輕鬆調用。它執行正則表達式搜索並替換stdin並將結果寫入stdout。它適用於所有現代版本的Windows,從XP開始。
你的任務是很容易使用REPL.BAT
假設每線有全部6個值,有效地實現(空值OK,但總是有5個分隔符):
type test.txt|repl "^[^|]*\|(.*)\|[^|]*$" "$1" >test.txt.new
move /y test.txt.new test.txt
如果某些線條缺失在結束值(丟失假定爲空值):
type test.txt|repl "(^[^|]*(\|[^|]*){4})\|[^|]*$" "$1"|repl "^[^|]*\|?(.*)$" "$1" >test.txt.new
move /y test.txt.new test.txt
這裏是REPL.BAT效用。它應該放在與批處理腳本和文件相同的文件夾中,或者放置在駐留在PATH中的文件夾中。腳本中內置了完整的文檔。
@if (@X)==(@Y) @end /* Harmless hybrid line that begins a JScript comment
::************ Documentation ***********
:::
:::REPL Search Replace [Options [SourceVar]]
:::REPL /?
:::
::: Performs a global search and replace operation on each line of input from
::: stdin and prints the result to stdout.
:::
::: Each parameter may be optionally enclosed by double quotes. The double
::: quotes are not considered part of the argument. The quotes are required
::: if the parameter contains a batch token delimiter like space, tab, comma,
::: semicolon. The quotes should also be used if the argument contains a
::: batch special character like &, |, etc. so that the special character
::: does not need to be escaped with ^.
:::
::: If called with a single argument of /? then prints help documentation
::: to stdout.
:::
::: Search - By default this is a case sensitive JScript (ECMA) regular
::: expression expressed as a string.
:::
::: JScript regex syntax documentation is available at
::: http://msdn.microsoft.com/en-us/library/ae5bf541(v=vs.80).aspx
:::
::: Replace - By default this is the string to be used as a replacement for
::: each found search expression. Full support is provided for
::: substituion patterns available to the JScript replace method.
::: A $ literal can be escaped as $$. An empty replacement string
::: must be represented as "".
:::
::: Replace substitution pattern syntax is documented at
::: http://msdn.microsoft.com/en-US/library/efy6s3e6(v=vs.80).aspx
:::
::: Options - An optional string of characters used to alter the behavior
::: of REPL. The option characters are case insensitive, and may
::: appear in any order.
:::
::: I - Makes the search case-insensitive.
:::
::: L - The Search is treated as a string literal instead of a
::: regular expression. Also, all $ found in Replace are
::: treated as $ literals.
:::
::: B - The Search must match the beginning of a line.
::: Mostly used with literal searches.
:::
::: E - The Search must match the end of a line.
::: Mostly used with literal searches.
:::
::: V - Search and Replace represent the name of environment
::: variables that contain the respective values. An undefined
::: variable is treated as an empty string.
:::
::: M - Multi-line mode. The entire contents of stdin is read and
::: processed in one pass instead of line by line.^anchors
::: the beginning of a line and $ anchors the end of a line.
:::
::: X - Enables extended substitution pattern syntax with support
::: for the following escape sequences:
:::
::: \\ - Backslash
::: \b - Backspace
::: \f - Formfeed
::: \n - Newline
::: \r - Carriage Return
::: \t - Horizontal Tab
::: \v - Vertical Tab
::: \xnn - Ascii (Latin 1) character expressed as 2 hex digits
::: \unnnn - Unicode character expressed as 4 hex digits
:::
::: Escape sequences are supported even when the L option is used.
:::
::: S - The source is read from an environment variable instead of
::: from stdin. The name of the source environment variable is
::: specified in the next argument after the option string.
:::
::************ Batch portion ***********
@echo off
if .%2 equ . (
if "%~1" equ "/?" (
findstr "^:::" "%~f0" | cscript //E:JScript //nologo "%~f0" "^:::" ""
exit /b 0
) else (
call :err "Insufficient arguments"
exit /b 1
)
)
echo(%~3|findstr /i "[^SMILEBVX]" >nul && (
call :err "Invalid option(s)"
exit /b 1
)
cscript //E:JScript //nologo "%~f0" %*
exit /b 0
:err
>&2 echo ERROR: %~1. Use REPL /? to get help.
exit /b
************* JScript portion **********/
var env=WScript.CreateObject("WScript.Shell").Environment("Process");
var args=WScript.Arguments;
var search=args.Item(0);
var replace=args.Item(1);
var options="g";
if (args.length>2) {
options+=args.Item(2).toLowerCase();
}
var multi=(options.indexOf("m")>=0);
var srcVar=(options.indexOf("s")>=0);
if (srcVar) {
options=options.replace(/s/g,"");
}
if (options.indexOf("v")>=0) {
options=options.replace(/v/g,"");
search=env(search);
replace=env(replace);
}
if (options.indexOf("l")>=0) {
options=options.replace(/l/g,"");
search=search.replace(/([.^$*+?()[{\\|])/g,"\\$1");
replace=replace.replace(/\$/g,"$$$$");
}
if (options.indexOf("b")>=0) {
options=options.replace(/b/g,"");
search="^"+search
}
if (options.indexOf("e")>=0) {
options=options.replace(/e/g,"");
search=search+"$"
}
if (options.indexOf("x")>=0) {
options=options.replace(/x/g,"");
replace=replace.replace(/\\\\/g,"\\B");
replace=replace.replace(/\\b/g,"\b");
replace=replace.replace(/\\f/g,"\f");
replace=replace.replace(/\\n/g,"\n");
replace=replace.replace(/\\r/g,"\r");
replace=replace.replace(/\\t/g,"\t");
replace=replace.replace(/\\v/g,"\v");
replace=replace.replace(/\\x[0-9a-fA-F]{2}|\\u[0-9a-fA-F]{4}/g,
function($0,$1,$2){
return String.fromCharCode(parseInt("0x"+$0.substring(2)));
}
);
replace=replace.replace(/\\B/g,"\\");
}
var search=new RegExp(search,options);
if (srcVar) {
WScript.Stdout.Write(env(args.Item(3)).replace(search,replace));
} else {
while (!WScript.StdIn.AtEndOfStream) {
if (multi) {
WScript.Stdout.Write(WScript.StdIn.ReadAll().replace(search,replace));
} else {
WScript.Stdout.WriteLine(WScript.StdIn.ReadLine().replace(search,replace));
}
}
}
是什麼時期?只是文件結束的指標?或者它真的是文件中的一個字符? – dbenham