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server/util/randStr.ts

@@ -0,0 +1,25 @@
+const charList = [
+    '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
+    'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j',
+    'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't',
+    'u', 'v', 'w', 'x', 'y', 'z',
+];
+
+export function randStr(len: number): string {
+    const result = [];
+    const charListLen = charList.length;
+    let isStart = true;
+
+    while(len > 0){
+        const randChrIdx = Math.floor(Math.random() * charListLen);
+        if(isStart){
+            if(randChrIdx == 0){
+                continue;
+            }
+            isStart = false;
+        }
+        result.push(charList[randChrIdx]);
+        len -= 1;
+    }
+    return result.join('');
+}