Create 随机字符串的生成.js

Rain120 · Apr 3, 2018 · e5de444 · e5de444
1 parent da1bd34
commit e5de444
Showing 1 changed file with 43 additions and 0 deletions.
diff --git a/随机字符串的生成.js b/随机字符串的生成.js
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+/**
+ * 实现指定个数的随机生成[a-zA-Z],[0-9],或者自定义是字符串
+ **/
+ // 不加自定义字符
+ function randomStr(len) {
+  var ret = '';
+  var randomChar = function () {
+    var str = Math.floor(Math.random() * 62);
+    if (str < 10) {
+      return str; // 0-9
+    } else if (str < 36) {
+      return String.fromCharCode(str + 55); //A-Z
+    } else {
+      return String.fromCharCode(str + 61); // a-z
+    }
+  }
+  while (ret.length < len) {
+    ret += randomChar();
+  }
+  return ret;
+ }
+
+//加上自定义字符
+function randomStr(len, charSet) {
+  var ret = '';
+  var charSetLen = 62 + charSet.length;
+  var randomChar = function () {
+    var str = Math.floor(Math.random() * charSetLen);
+    if (str < 10) {
+      return str; // 0-9
+    } else if (str < 36) {
+      return String.fromCharCode(str + 55); //A-Z
+    } else if (str < 62) {
+      return String.fromCharCode(str + 61); // a-z
+    } else {
+        return charSet[charSetLen - str - 1]
+    }
+  }
+  while (ret.length < len) {
+    ret += randomChar();
+  }
+  return ret;
+ }