Cov txheej txheem:
- Sau rau Cov Ntawv Teev Npe hauv Java
- Cia peb xav txog cov kauj ruam los qhib cov ntaub ntawv CSV yooj yim thiab txheeb xyuas cov ntaub ntawv nws muaj:
Video: Koj sau thiab ntxiv rau cov ntaub ntawv hauv Java li cas?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Java append rau ntaub ntawv . Peb ua tau ntxiv rau file hauv java siv cov chav kawm nram qab no. Yog tias koj ua haujlwm ntawm cov ntaub ntawv cov ntaub ntawv thiab cov naj npawb ntawm sau kev khiav hauj lwm tsawg dua, siv FileWriter thiab siv nws cov constructor nrog ntxiv chij tus nqi raws li qhov tseeb. Yog tus naj npawb ntawm sau kev ua haujlwm loj heev, koj yuav tsum siv BufferedWriter.
Raws li, koj yuav ua li cas ntxiv rau cov ntaub ntawv uas twb muaj lawm hauv Java?
Koj ua tau ntxiv text in ib cov ntaub ntawv uas twb muaj lawm hauv Java los ntawm qhib a ntaub ntawv siv FileWriter chav kawm hauv ntxiv hom. Koj tuaj yeem ua qhov no los ntawm kev siv tus tsim tshwj xeeb muab los ntawm FileWriter chav kawm, uas lees txais a ntaub ntawv thiab ib tug boolean, uas yog dhau li qhov tseeb ces qhib lub ntaub ntawv hauv ntxiv hom.
Kuj Paub, Kuv yuav ua li cas ntxiv rau cov ntawv nyeem? Rau ntxiv rau cov ntawv nyeem Siv txoj kev WriteAllText, qhia meej lub hom phiaj ntaub ntawv thiab txoj hlua yuav tsum tau ntxiv thiab teeb tsa ntxiv parameter rau True. Qhov piv txwv no sau txoj hlua "Qhov no yog txoj hlua xeem." mus rau ntaub ntawv npe Testfile. txt.
Ua raws li qhov no, koj yuav ua li cas ntxiv cov ntawv rau cov ntaub ntawv hauv Java?
Sau rau Cov Ntawv Teev Npe hauv Java
- import java.io. FileWriter;
- pej xeem WriteFile(String file_path, boolean append_value) {
- path = file_path;
- }
- FileWriter sau = tshiab FileWriter(path, append_to_file);
- PrintWriter print_line = tshiab PrintWriter(sau);
- print_line.
- print_line.printf("%s" + "%n", textLine);
Kuv yuav ua li cas ntxiv cov ntaub ntawv csv hauv Java?
Cia peb xav txog cov kauj ruam los qhib cov ntaub ntawv CSV yooj yim thiab txheeb xyuas cov ntaub ntawv nws muaj:
- Siv FileReader qhib cov ntaub ntawv CSV.
- Tsim BufferedReader thiab nyeem cov ntaub ntawv kab los ntawm kab kom txog thaum "End of File" (EOF) cim.
- Siv txoj hlua. split() txoj hauv kev los txheeb xyuas qhov comma delimiter thiab faib cov kab rau hauv daim teb.
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