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

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

file.getSandBoxDir Get Sandbox Directory Path

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

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

file.getSandBoxFilePath Get Sandbox File Path

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

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

file.readFile Read as String

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

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

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

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

file.listDir List All Files

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

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

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

file.writeFile Write File

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

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

file.create Create File

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

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

file.mkdirs Create Directory

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

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

file.deleteAllFile Delete

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

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

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

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

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

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

file.readAllLines Read All Lines

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

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

file.exists Check Existence

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

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

file.copy Copy File

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

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