文件的读/写

/写入文件,数据集ClientDataSet1里有a，b，c三个字段

if (ClientDataSet1->IsEmpty())

{

ShowMessage("文件没有内容可以写入！")；

return;

}

SaveDialog1->Title = "选择路径名："；

SaveDialog1->FileName = "模块名" + Date().FormatString("yyyymmdd");

SaveDialog1->DefaultExt = "txt";

SaveDialog1->Filter = "文本文件（*.txt）|(*.txt)|所有文件（*.*）|(*.*)";

ClientDataSet1->First();

while (!ClientDataSet1->Eof)

{

File * fp = fopen(SaveDialog1->FieldName,"wt");

fprintf(fp, "%s\t", ClientDataSet1->FieldByName("a")->AsString.Trim());

fprintf(fp, "%s\t", ClientDataSet1->FieldByName("b")->AsString.Trim());

fprintf(fp, "%s\n", ClientDataSet1->FieldByName("c")->AsString.Trim());

ClientDataSet1->Next();

}

fclose(fp);

ShowMessage("写入文件成功！")；

//读取文件，存储到数据集ClientDataSet1的a，b，c字段中

int i=0,ch,ntype=0;

char str[256];

AnsiString a,b,c;

File * fp = fopen(OpenDialog->FileName,"rt");

ClientDataSet1->EmptyDataSet();

while ((ch = fgetc(fp))!=Eof)

switch(ch)

{

case '\t':

str[ntype] = '\0';

switch(i):

{

case 0: a = str;break;

case 1: b = str;break;

case 2: c = str;bread;

}

i++;

ntype = 0;

break;

case '\n':

str[ntype] = '\0';

ClientDataSet1->Insert();

ClientDataSet1->FieldByName("a")->AsString = a.Trim();

ClientDataSet1->FieldByName("b")->AsString = a.Trim();

ClientDataSet1->FieldByName("c")->AsString = a.Trim();

i = 0;

n = 0;

break;

default:

str[ntype] = ch;

ntype++;

}

fclose(fp);

ClientDataSet1->Post();

ShowMessage("读取文件成功！");