C++Builder之AnsiString常用方法

AnsiString常用用法

LastDelimiter(const AnsiString& delimiters)

Returns the index of the rightmost character that matches any character in the delimiters string.

获取字符串中与delimiters相匹配的字符的index，例如：

strtxt = “ab.hig”

uiIndex = strtxt.LastDelimiter(".");

//uiIndex为3.

如果出现多个delimiters，以最后一个为准

strtxt = “abafa”

uiIndex = strtxt.LastDelimiter("a");

//uiIndex为5.

AnsiPos

int __fastcall AnsiPos(const AnsiString& subStr) const;

Returns the index in the AnsiString at which the substring subStr begins, where 1 is the first character in the string, 2 is the second character, and so on. If the substring is not contained in the AnsiString, Pos returns 0. This member function is the same as Pos but supports multibyte character strings.

AnsiPos与LastDelimiter得区别是：前者输出第一个相同字符串的index；后者输出最后一个相同的index

LowerCase() const; UpperCase() const;

将一个字符串转化为小字符或者大字符；

AnsiCompareIC && AnsiCompare

比较两个字符串；相同为0，例如

AnsiString strTxt;

int strTxt;

strTxt = "abc";

cmpRlst = strTxt.AnsiCompareIC("abc"); //cmpRlst结果为0

两个命令的区别是，AnsiCompareIC 忽略大小写，AnsiCompare需要考虑大小写

//Ansistring 转 char
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   AnsiString Test = "哈哈";
   char *chr = Test.c_str();
}

//char转Ansistring
#include <windef.h>
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   AnsiString str = "Sample";
   char chr[MAX_PATH];
   strcpy( chr , str.c_str() );
}

//Bool转AnsiString
void __fastcall TForm1::Button1Click(TObject *Sender)
{
AnsiString Test=BoolToStr(CheckBox1->Checked);
}

//Ansistring转bool
void __fastcall TForm1::Button1Click(TObject *Sender)
{ AnsiString Test="-1"
   CheckBox1->Checked= StrToBool( Test );
}

//int转ansistring
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   int i = 123;
   AnsiString str = IntToStr( i );
}

//AnsiString转double
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   AnsiString Test = "123";
   long double d = StrToFloat( Test );
}

//double转AnsiString
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   double d = 123.456;
   AnsiString str = FloatToStr( d );
}

//double转AnsiString并四舍五入
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   long double d = 123.456121212;
   AnsiString str = FloatToStrF( d , ffFixed ,5 , 4 );
//说明FloatTostrF里5代表从第几个数字的后一位开始四舍五入,4代表取4位小数。
//执行后得到str是123.4600。:roll:

}

//double转AnsiString使用类似vb的format函数
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   double d = 123.456;
   AnsiString str = FormatFloat( "000000.00" , d );
}
//得到 000123.45，当然你可以使用"# . , ; E+ E- xx"等符号，你自己试试 :wink:

//AnsiString转Tclor型
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   AnsiString Test = "0x00FF8080";
   TColor Col = StringToColor( Test );
}

//Tcolor转AnsiString
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   TColor Col = 0x00FF8080;
   AnsiString str = ColorToString( Col );
}

//消除AnsiString 中的一部分字符串 代码:
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   AnsiString Test = "ABCDEF";
   int First = 3;     // 消除制定开头
   int Length = 2;    // 消除制定长度
   AnsiString Dstr = Test.Delete( First , Length );
}//得到ABEF

//在AnsiString 中插入字符串
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   AnsiString Test = "ABCDEF";
   AnsiString Ins = "12345";     // 插入串
   int Pos = 3;                  // 在哪插
   AnsiString Istr = Test.Insert( Ins , Pos );
//得到AB12345CDEF
}

//取得ansi某一位字符
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   AnsiString Test = "ABCDEF";
   AnsiString Npos = Test[3];//得到C
}

//取得AnsiString里最后一个字符
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   AnsiString Test = "ABCDEF";
   char *Lstr = Test.AnsiLastChar();//得到F
}

//取出AnsiString字符，这个类似vb的mid函数！
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   AnsiString Test = "ABCDEF";
   int First = 3;     // 3开始取
   int Length = 2;    // 取2位
   AnsiString Getstr = Test.SubString( First , Length );
//得到CD
}

//AnsiString的字母比较
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   AnsiString Test = "ABCDEF";
   AnsiString Sample = "abcdef";
   int Result = Test.AnsiCompare( Sample );
//返回1，不同！分大小写。
}

void __fastcall TForm1::Button1Click(TObject *Sender)
{
   AnsiString Test = "ABCDEF";
   AnsiString Sample = "abcdef";
   int Result = Test.AnsiCompareIC( Sample );
//返回0，相同！没有分大小写，哈哈
}

//在AnsiString中寻找字符
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   AnsiString Test = "ABCDEF";
   AnsiString Sample = "E";
   int Result = Test.Pos( Sample );
//返回5，如果你写Sample＝"haha",就返回0，找不到，哈哈
}

//在AnsiString中找字符串，和上一个类似
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   AnsiString Test = "ABCDEF";
   AnsiString Sample = "EF";
   int Result = Test.Pos( Sample );
//返回5，即E字符的位置
}

//判断字符串长度，类似vb的len
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   AnsiString Test = "拿金币来";
   int Len = Test.Length();
//返回8
}

//取得字符串，类似vb的left
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   AnsiString Test = "小苹果然看了这篇文章";
   AnsiString SLstr = Test.SetLength(6);
}//得到"小苹果"

//检测双字节字串
void __fastcall TForm1::Button1Click(TObject *Sender)
{
AnsiString ChkStr = "你好";
int ChkPos =  1  ;
if ( ByteType( ChkStr , ChkPos ) == mbSingleByte ){
   Edit1->Text="0";
   }
   else{
   Edit1->Text="1";
   }//返回1，如果你写ChkStr＝"fxxk"，就返回0
}

//检测空字符串
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   AnsiString Test = "";
   bool chk = Test.IsEmpty();
   if (chk )
   Edit1->Text="1";//返回1
}

//全部变小写vs全部变大写
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   AnsiString Test = "ABCdef";
   AnsiString Lstr = Test.LowerCase();
}

代码:

void __fastcall TForm1::Button1Click(TObject *Sender)
{
   AnsiString Test = "ABCdef";
   AnsiString Ustr = Test.UpperCase();
}

//类似vb中Trim 的去空格函数
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   AnsiString Test = "     ABCDEF      ";
   AnsiString TLstr = Test.TrimLeft();
  AnsiString TRstr = Test.TrimRight();
 AnsiString Tstr = Test.Trim();
}

//但是，这个处理不了全角的空格 代码:
AnsiString __fastcall TForm1::TrimStr( AnsiString Tm , AnsiString LR )
{
   // LR … L:左除去   R:右除去   B:dou除去
   int len;
   // 左除去
   if ( LR == "L" || LR == "B" ){
       len = Tm.Length();
       while ( Tm.SubString(1,1) == " " || Tm.SubString(1,2) == "　"){
           // 半角除去
           if ( Tm.SubString(1,1) == " " ){
               Tm = Tm.SubString(2,len);
               len = Tm.Length();
           }
           // 全角除去
           else if ( Tm.SubString(1,2) == "　" ){
               Tm = Tm.SubString(3,len);
               len = Tm.Length();
           }
       }
   }
   // 右除去
   if ( LR == "R" || LR == "B" ){
       len = Tm.Length();
       while ( Tm.SubString(len,1) == " " || Tm.SubString(len-1,2) == "　" ){
           // 半角除去
           if ( Tm.SubString(len,1) == " " ){
               len = Tm.Length();
               Tm = Tm.SubString(1,len-1);
               len = Tm.Length();
           }
           // 全角除去
           else if ( Tm.SubString(len-1,2) == "　" ){
               len = Tm.Length();
               Tm = Tm.SubString(1,len-2);
               len = Tm.Length();
           }
       }
   }
   return Tm;
}
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   AnsiString Test = "　　拳脚　　";
   AnsiString Ret = TrimStr(Test,"B")
}

//相同字符重复输入
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   AnsiString Soc = AnsiString::StringOfChar( '*' , 100 );
  Edit1->Text=Soc ;//显示100个*

}

//字符串替换
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   AnsiString Str = "Borland C++ Builder is free";
   AnsiString From = "C++ Builder";                    
   AnsiString To = "Delphi";                            
   AnsiString Result;                                    
   Result = StringReplace( Str, From, To, TReplaceFlags() <<
rfReplaceAll << rfIgnoreCase );
//<<后是参数，得到Borland Delphi is free
}

//全角变半角
   AnsiString Zen = "１２３４５６７８９０";
   int Len = Zen.Length();
   char buf[MAX_PATH];
   ZeroMemory( buf, sizeof( buf ) );
   LCMapString( GetUserDefaultLCID(), LCMAP_HALFWIDTH, Zen.c_str(), Len, buf, sizeof( buf ) );
   AnsiString Han = AnsiString( buf );
   Edit1->Text=Han;

//半角变全角
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   AnsiString Han = "1234567890";
   int Len = Han.Length();
   char buf[MAX_PATH];
   ZeroMemory( buf, sizeof( buf ) );
   LCMapString( GetUserDefaultLCID(), LCMAP_FULLWIDTH, Han.c_str(), Len, buf, sizeof( buf ) );
   AnsiString Zen = AnsiString( buf );
}