File Functions

Overview

• File module functions are related to file operations
• The file module uses the file prefix, e.g. file.readFile()
• To get a file path inside the device sandbox, use file.getSandBoxFilePath()

file.getInternalDir Get Internal Storage Path

• Get internal storage path
• @param type — documents, library, temp, or libraryCaches; the documents folder can be exported via iTools/i4
• @return string

function main() {
    var data = file.getInternalDir("documents");
    logd(data);
}

main();

file.getSandBoxDir Get Sandbox Directory Path

• Get the current device sandbox directory path
• @return string

function main() {
    var data = file.getSandBoxDir();
    logd(data);
}

main();

file.getSandBoxFilePath Get Sandbox File Path

• Build a file path under the sandbox
• @return string

function main() {
    var data = file.getSandBoxFilePath("a.txt");
    logd(data);
}

main();

file.readFile Read as String

• Read a file as a string
• @param path file path
• @return string

function main() {
    let p = file.getSandBoxFilePath("a.txt");
    var data = file.readFile(p);
    logd(data);
}

main();

file.deleteLine Delete a Line from File

• Delete a specific line or lines matching a substring
• Runtime: no restrictions
• @param path file path
• @param line line number; -1 disables this condition
• @param contains delete lines containing this string; null disables this condition
• @return {bool} true on success, false on failure

function main() {
    let p = file.getSandBoxFilePath("a.txt");
    // Delete lines containing "time"
    let r = file.deleteLine(p, -1, "time");
    logd("r " + r);
    // Delete line 3
    r = file.deleteLine(p, 3, null);
    logd("r " + r);
}

main();

file.deleteLineEx Delete a Line from File (Extended)

• Delete a specific line or lines matching a substring
• Suitable for large files
• Requires EC 4.7.3+
• @param path file path
• @param line line number; -1 disables this condition
• @param contains delete lines containing this string; null disables this condition
• @return {bool} true on success, false on failure

function main() {
    let p = file.getSandBoxFilePath("a.txt");
    // Delete lines containing "time"
    let r = file.deleteLineEx(p, -1, "time");
    logd("r " + r);
    // Delete line 3
    r = file.deleteLineEx(p, 3, null);
    logd("r " + r);
}

main();

file.listDir List All Files

• List all files under a path (recursive)
• @param path directory path
• @return array of path strings

function main() {
    let p = file.getSandBoxDir();
    var data = file.listDir(p);
    for (var i = 0; i < data.length; i++) {
        logd("path " + data[i]);
    }
}

main();

file.listDir2 List Files (Recursive Option)

• List files and folders under a path
• Requires EC standalone 4.1.0+
• @param path directory path
• @param recursion true to recurse into subfolders, false to list only the immediate directory
• @return array of path strings

function main() {
    let p = file.getSandBoxDir();
    var data = file.listDir2(p, false);
    for (var i = 0; i < data.length; i++) {
        logd("path " + data[i]);
    }
}

main();

file.writeFile Write File

• Write a string to a file
• @param data string data
• @param path file path

function main() {
    var data = "Test";
    let p = file.getSandBoxFilePath("a.txt");
    file.writeFile(data, p);
}

main();

file.create Create File

• Create a file
• @param path file path
• @return boolean — true if created successfully

function main() {
    let p = file.getSandBoxFilePath("a.txt");
    var create = file.create(p);
    logd(create);
}

main();

file.mkdirs Create Directory

• Create a directory
• @param path directory path
• @return boolean — true on success, false on failure

function main() {
    let p = file.getSandBoxDir();
    p = p + "/ad"
    var t = file.mkdirs(p);
    logd(t);
}

main();

file.deleteAllFile Delete

• Delete a file or directory
• @param path file or directory path

function main() {
    // Delete file
    let filePath = file.getSandBoxFilePath("a.txt");
    file.deleteAllFile(filePath);
    // Delete folder
    let dirPath = file.getSandBoxFilePath("a/");
    file.deleteAllFile(dirPath);
}

main();

file.appendLine Append Line

• Append a line to a file
• @param data line data
• @param path file path
• @return boolean — true on success, false on failure

function main() {
    var data = "sss";
    let p = file.getSandBoxFilePath("a.txt");
    var t = file.appendLine(data, p);
    logd(t);
}

main();

file.appendLineEx Append Line (Extended)

• Append a line to a file
• Suitable for large files
• Requires EC 4.7.3+
• @param data line data
• @param path file path
• @return boolean — true on success, false on failure

function main() {
    var data = "sss";
    let p = file.getSandBoxFilePath("a.txt");
    var t = file.appendLineEx(data, p);
    logd(t);
}

main();

file.readLine Read One Line

• Read one line; returns empty if the line number is invalid
• @param path file path
• @param lineNo line number (1-based)
• @return string

function main() {
    let p = file.getSandBoxFilePath("a.txt");
    var t = file.readLine(p, 1);
    logd(t);
}

main();

file.readLineEx Read One Line (Extended)

• Read one line; returns empty if the line number is invalid
• Suitable for large files
• Requires EC 4.7.3+
• @param path file path
• @param lineNo line number (1-based)
• @return string

function main() {
    let p = file.getSandBoxFilePath("a.txt");
    var t = file.readLineEx(p, 1);
    logd(t);
}

main();

file.readAllLines Read All Lines

• Read all lines
• @param path file path
• @return string array or null

function main() {
    let p = file.getSandBoxFilePath("a.txt");
    var t = file.readAllLines(p);
    logd(t);
}

main();

file.exists Check Existence

• Whether a file or directory exists
• @param path path
• @return boolean — true if exists, false otherwise

function main() {
    let p = file.getSandBoxFilePath("a.txt");
    var t = file.exists(p);
    logd(t);
}

main();

file.copy Copy File

• Copy a file
• @param src source file path
• @param dest destination file path
• @return boolean — true on success

function main() {
    let p1 = file.getSandBoxFilePath("a1.txt");
    let p2 = file.getSandBoxFilePath("a2.txt");
    var t = file.copy(p1, p2);
    logd(t);
}

main();