我编写了一个脚本，用于将文本文件中的分号分隔符替换为逗号，但它也会在第9列的文本周围添加引号，因为第9列包含逗号。当我输出到新文本文件时它处理速度非常慢，大约需要4-5分钟，它正在读取的文本文件是50MB。有没有更快的方式或更有效的方法来做到这一点？这是我的FOR循环：
FOR /f "usebackq tokens=1-9* delims=;" %%a IN ("%FILENAME%") DO (
SET C10=%%j
ECHO(%%a,%%b,%%c,%%d,%%e,%%f,%%g,%%h,"%%i",!C10:;=,! >> "%MYPATH%\Filename %MMDDYYYY%.csv")
或者我应该学习python .....
谢谢。
答案 0 :(得分：6)
使脚本运行＆＃34;更快＆＃34; 的一件事是避免为每次写操作打开和关闭输出文件
>> "%MYPATH%\Filename %MMDDYYYY%.csv" (
FOR /f "usebackq tokens=1-9* delims=;" %%a IN ("%FILENAME%") DO (
SET C10=%%j
ECHO(%%a,%%b,%%c,%%d,%%e,%%f,%%g,%%h,"%%i",!C10:;=,!
)
)
不是重定向每一行，而是重定向完整的for命令。
答案 1 :(得分：4)
如果要更改分隔符以在Excel中正确打开csv：无需执行此操作。有一个（未记录的）技巧告诉Excel，使用什么字符作为分隔符：
(echo Sep=;) > new.csv
type old.csv >> new.csv
move /y new.csv old.csv
注意：Excel会读取Sep=;，并使用该分隔符导入文件的其余部分，但它不属于传播文件的一部分，因此如果再次使用Excel保存，{{1}丢失（Excel使用Sep=;或,作为分隔符，具体取决于它的安装语言。
答案 2 :(得分：1)
Squashman最好使用我的parseCSV.bat utility进行转换。该实用程序是一个混合脚本，它使用批处理和JScript。该实用程序比任何纯批处理解决方案都快得多，并且它可以在任何Windows机器上从XP开始本地运行 - 不需要第三方exe。
该实用程序实际上是为了在批处理文件中通过FOR / F方便地解析CSV文件而生成的。版本1.0有一个问题，使得使用该实用程序转换CSV格式以用于其他用途不太理想 - 转义的引用文字未转义，因此＆＃34;＆＃34;成为＆＃34;。此转换对于FOR / F解析很有用，但它不是有效的CSV格式。
我修改了该实用程序，以便选择保留引号文字的转义。现在，您可以安全地使用以下内容快速从分号转换为逗号分隔符。
call parseCSV因为parseCSV本身就是一个批处理脚本，所以如果在另一个批处理脚本中使用该命令，则必须使用@if (@X)==(@Y) @end /* harmless hybrid line that begins a JScrpt comment
::************ Documentation ***********
::parseCSV.bat version 1.2
:::
:::parseCSV [/option]...
:::
::: Parse stdin as CSV and write it to stdout in a way that can be safely
::: parsed by FOR /F. All columns will be enclosed by quotes so that empty
::: columns may be preserved. It also supports delimiters, newlines, and
::: escaped quotes within quoted values. Two consecutive quotes within a
::: quoted value are converted into one quote by default.
:::
::: Available options:
:::
::: /I:string = Input delimiter. Default is a comma (,)
:::
::: /O:string = Output delimiter. Default is a comma (,)
:::
::: The entire option must be quoted if specifying poison character
::: or whitespace literals as a delimiters for /I or /O.
:::
::: Examples: pipe = "/I:|"
::: space = "/I: "
:::
::: Standard JScript escape sequences can also be used.
:::
::: Examples: tab = /I:\t or /I:\x09
::: backslash = /I:\\
:::
::: /E = Encode output delimiter literal within value as \D
::: Encode newline within value as \N
::: Encode backslash within value as \S
:::
::: /D = escape exclamation point and caret for Delayed expansion
::: ! becomes ^!
::: ^ becomes ^^
:::
::: /L = treat all input quotes as quote Literals
:::
::: /Q:QuoteOutputFormat
:::
::: Controls output of Quotes, where QuoteOutputFormat may be any
::: one of the following:
:::
::: L = all columns quoted, quote Literals output as " (Default)
::: E = all columns quoted, quote literals Escaped as ""
::: N = No columns quoted, quote literals output as "
:::
::: The /Q:E and /Q:N options are useful for transforming data for
::: purposes other than parsing by FOR /F
:::
::: /U = Write unix style lines with newline (\n) instead of the default
::: Windows style of carriage return and linefeed (\r\n).
:::
:::parseCSV /?
:::
::: Display this help
:::
:::parseCSV /V
:::
::: Display the version of parseCSV.bat
:::
:::parseCSV.bat was written by Dave Benham. Updates are available at the original
:::posting site: http://www.dostips.com/forum/viewtopic.php?f=3&t=5702
:::
::************ Batch portion ***********
@echo off
if "%~1" equ "/?" (
setlocal disableDelayedExpansion
for /f "delims=: tokens=*" %%A in ('findstr "^:::" "%~f0"') do echo(%%A
exit /b 0
)
if /i "%~1" equ "/V" (
for /f "delims=:" %%A in ('findstr /bc:"::%~nx0 version " "%~f0"') do echo %%A
exit /b 0
)
cscript //E:JScript //nologo "%~f0" %*
exit /b 0
************ JScript portion ***********/
var args = WScript.Arguments.Named,
stdin = WScript.Stdin,
stdout = WScript.Stdout,
escape = args.Exists("E"),
literalQ = args.Exists("L"),
escapeQ = (args.Item("Q")&&args.Item("Q").toUpperCase()=="E"),
quoteCol = (args.Item("Q")&&args.Item("Q").toUpperCase()=="N") ? '' : '"',
delayed = args.Exists("D"),
inDelim = args.Item("I") ? eval('"'+args.Item("I")+'"') : ",",
outDelim = args.Item("O") ? eval('"'+args.Item("O")+'"') : ",",
newline = args.Exists("U") ? "\n" : "\r\n",
quote = false,
ln, c, n, out;
while (!stdin.AtEndOfStream) {
ln=stdin.ReadLine();
out="";
if (!quote) stdout.Write(quoteCol);
for (n=0; n<ln.length; n++ ) {
c=ln.charAt(n);
if (c == '"') {
if (literalQ) {
if (escapeQ) c+='"';
} else if (quote && ln.charAt(n+1) == '"') {
n++;
if (escapeQ) c+='"';
} else {
quote=!quote;
continue;
}
}
else if (c == inDelim && !quote) c=quoteCol+outDelim+quoteCol;
else if (escape) {
if (c == outDelim) c="\\D";
if (c == "\\") c="\\S";
}
else if (delayed) {
if (c == "!") c="^!";
if (c == "^") c="^^";
}
out+=c;
}
out += (quote) ? ((escape) ? "\\N" : newline) : quoteCol+newline;
stdout.Write(out);
}
。
我能够在2.5分钟内使用parseCSV.bat转换53MB文件。
以下是parseCSV的代码。但是，我不保证将此代码保持最新。我建议您从DosTips post获取代码。在那里，您还可以找到该实用程序其他功能的良好描述。
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.layout.Pane;
import javafx.scene.shape.Line;
import javafx.stage.Stage;
/**
*
* @author Sedrick
*/
public class DrawTriangle extends Application {
@Override
public void start(Stage primaryStage) {
//I changed the points to make processing easier. I also add 100 to each point so that the output looks better.
String[] points = {"100.350:100.890", "300.825:300.330", "300.915:100.575", "200.385:300.690",
"100.350:200.295", "400.545:100.845", "200.250:100.710", "400.140:300.060",
"200.250:300.150", "300.465:100.755"};
Set<String> distinctPoints = new HashSet(Arrays.asList(points));//Keep only distinct points
List<String> distincePointsList = new ArrayList<String>(distinctPoints); //Make the distinct points gettable
Button btn = new Button();
btn.setText("Press me!");
Pane root = new Pane();
root.getChildren().add(btn);
btn.setOnAction(new EventHandler<ActionEvent>() {
@Override
public void handle(ActionEvent event) {
for(int i = 0; i < distincePointsList.size() - 3; i++)
{
for(int t = i + 1; t < distincePointsList.size() - 2; t++)
{
for(int s = t + 1; s < distincePointsList.size() - 1; s++)
{
root.getChildren().addAll(drawTriangle(distincePointsList.get(i), distincePointsList.get(t), distincePointsList.get(s))); //get the three points and return a triangle made by the lines drawn from point to point
}
}
}
}
});
Scene scene = new Scene(root, 1080, 720);
primaryStage.setTitle("Hello World!");
primaryStage.setScene(scene);
primaryStage.show();
}
/**
* @param args the command line arguments
*/
public static void main(String[] args) {
launch(args);
}
//Creates drawing of lines that form triangle. returns an list of the 3 lines
static List drawTriangle(String p1, String p2, String p3)
{
List<Line> lineHolder = new ArrayList();
String[] tempP1 = p1.split(":");
String[] tempP2 = p2.split(":");
String[] tempP3 = p3.split(":");
Line line1 = new Line();
line1.setStartX(Float.parseFloat(tempP1[0]));
line1.setStartY(Float.parseFloat(tempP1[1]));
line1.setEndX(Float.parseFloat(tempP2[0]));
line1.setEndY(Float.parseFloat(tempP2[1]));
lineHolder.add(line1);
Line line2 = new Line();
line2.setStartX(Float.parseFloat(tempP2[0]));
line2.setStartY(Float.parseFloat(tempP2[1]));
line2.setEndX(Float.parseFloat(tempP3[0]));
line2.setEndY(Float.parseFloat(tempP3[1]));
lineHolder.add(line2);
Line line3 = new Line();
line3.setStartX(Float.parseFloat(tempP3[0]));
line3.setStartY(Float.parseFloat(tempP3[1]));
line3.setEndX(Float.parseFloat(tempP1[0]));
line3.setEndY(Float.parseFloat(tempP1[1]));
lineHolder.add(line3);
return lineHolder;
}
}