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更改.txt文件并用powershell保存

powershell

Stefan0309 · 技术社区 · 6 年前

我正在用powershell在一些.txt文件中执行经典的查找和替换。如何在结尾处“保存”文件?我试过设置内容,但什么也没发生。也许我需要先添加内容?

#Find what?
$optionBuilderStringToFind = "optionsBuilder.UseSqlServer"
$findUsingKeywordString = "using Microsoft."

#Replace with
$namespaceAdd = "using Microsoft.Extensions.Configuration;"
$optionBuilderConfigurable ="optionsBuilder.UseSqlServer(_configuration.GetConnectionString(`"Database`") 
 );"

gc -Path .\APSContext.cs | % { 
if ($_ -match "using System;") {
    $_ = $_ + "`n" + $namespaceAdd
    #write-host $_
}
if ($_ -match "optionsBuilder.UseSqlServer") {
    $_ = $optionBuilderConfigurable
    #write-host $_
}
} | Set-Content -Path .\test.cs

更新:这是一个测试文件,我正在修改它。文件的内容并不重要。我想添加另一个引用,比如“using something.something”,并在文件中间替换 "optionsBuilder.UseSqlServer("dfjidfjljfiejf88");" 具有 "optionsBuilder.UseSqlServer("_configtest");" :

using System;
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Metadata;

namespace SRC.APS.Model.APSDB
{
public partial class APSContext : DbContext
{
    public APSContext()
    {
    }

    public APSContext(DbContextOptions<APSContext> options)
        : base(options)
       protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
    {
        if (!optionsBuilder.IsConfigured)
        {

            optionsBuilder.UseSqlServer("dfjidfjljfiejf88");
        }
    }

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        modelBuilder.HasAnnotation("ProductVersion", "2.2.0-rtm-35687");

    }

也许我需要用绳子代替?

2 回复 | 直到 6 年前

Tomalak 6 年前

powershell中的任何脚本块都可以生成值。这是由不在变量中存储值:

{ $foo = 3 } 一无所获
{ 3 } 产生整数 3 .

以同样的方式

ForEach-Object { $_ = "something" } 一无所获
ForEach-Object { $_ = "something"; $_ } 生成字符串 "something"

循环体不输出任何内容,就像上面的示例一样。因此, Set-Content 无事可做。修改块以实际返回 $_ :

$replacements = @(
    @{regex='using (System|Potentially|Others);'; replacement='using Microsoft.$1;' }
    @{regex='optionsBuilder\.UseSqlServer\("[^"]*"\)'; replacement='optionsBuilder.UseSqlServer("Database")' }
    # more search/replace pairs
)

Get-Content .\APSContext.cs -Encoding UTF8 | ForEach-Object {
    foreach ($item in $replacements) {
        $_ = $_ -replace $item.regex, $item.replacement
    }
    $_   # <--- this is what produces the line
} | Set-Content -Path .\test.cs -Encoding UTF8

也就是说,不要加载或保存没有指定编码的文本文件。对于c源代码文件,我认为utf-8是默认的。

和那个也就是说,用正则表达式修改源代码不是一件好事。如果这是一次性的,可以。如果你打算定期这样做,那你就做错了。使用配置文件或环境变量,而不是保存在代码基文本值中,这些值会定期更改。

Lee_Dailey 6 年前

正如我所提到的——正如托马拉克所指出的——你对当前管道对象的干扰是问题的根源。[ 露齿而笑 ]这段代码修复了if cascade中的一个逻辑错误[使用 switch 阻止],消除不明智 $_ 摆弄,然后确保总是有一些输出。

# fake reading in a text file
#    in real life, use Get-Content
$InStuff = @'
using System;
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Metadata;

namespace SRC.APS.Model.APSDB
{
public partial class APSContext : DbContext
{
    public APSContext()
    {
    }

    public APSContext(DbContextOptions<APSContext> options)
        : base(options)
       protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
    {
        if (!optionsBuilder.IsConfigured)
        {

            optionsBuilder.UseSqlServer("dfjidfjljfiejf88");
        }
    }

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        modelBuilder.HasAnnotation("ProductVersion", "2.2.0-rtm-35687");

    }
'@ -split [environment]::NewLine

#Find what?
$optionBuilderStringToFind = "optionsBuilder.UseSqlServer"
$findUsingKeywordString = "using Microsoft."

#Replace with
$namespaceAdd = 'using Microsoft.Extensions.Configuration;'
$optionBuilderConfigurable ='optionsBuilder.UseSqlServer(_configuration.GetConnectionString("Database"));'

$InStuff | ForEach-Object { 
    if ($_ -match "using System;")
        {
        $_ + "`n" + $namespaceAdd
        #write-host $_
        }
        elseif ($_ -match "optionsBuilder.UseSqlServer")
        {
        $optionBuilderConfigurable
        #write-host $_
        }
        else
        {
        $_
        }
    }

输出…

using System;
using Microsoft.Extensions.Configuration;
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Metadata;

namespace SRC.APS.Model.APSDB
{
public partial class APSContext : DbContext
{
    public APSContext()
    {
    }

    public APSContext(DbContextOptions<APSContext> options)
        : base(options)
       protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
    {
        if (!optionsBuilder.IsConfigured)
        {

optionsBuilder.UseSqlServer(_configuration.GetConnectionString("Database"));
        }
    }

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        modelBuilder.HasAnnotation("ProductVersion", "2.2.0-rtm-35687");

    }