diff --git a/packages/core/__tests__/lib/core-is.test.ts b/packages/core/__tests__/lib/core-is.test.ts
index 66f8492..b5c5fc0 100644
--- a/packages/core/__tests__/lib/core-is.test.ts
+++ b/packages/core/__tests__/lib/core-is.test.ts
@@ -44,4 +44,98 @@ describe("@idraw/core static is", () => {
     expect(Core.is.angle(-370)).toStrictEqual(false);
   });
 
+  test('Core.is.borderWidth', () => {
+    expect(Core.is.borderWidth(0)).toStrictEqual(true);
+    expect(Core.is.borderWidth(100)).toStrictEqual(true);
+    expect(Core.is.borderWidth(-100)).toStrictEqual(false);
+    expect(Core.is.borderWidth(-370)).toStrictEqual(false);
+  });
+
+  test('Core.is.borderRadius', () => {
+    expect(Core.is.borderRadius(0)).toStrictEqual(true);
+    expect(Core.is.borderRadius(100)).toStrictEqual(true);
+    expect(Core.is.borderRadius(-100)).toStrictEqual(false);
+    expect(Core.is.borderRadius(-370)).toStrictEqual(false);
+  });
+
+  test('Core.is.color', () => {
+    expect(Core.is.color('#a23')).toStrictEqual(true);
+    expect(Core.is.color('#a2312f')).toStrictEqual(true);
+    expect(Core.is.color('#a2312')).toStrictEqual(false);
+    expect(Core.is.color('#a2')).toStrictEqual(false);
+  });
+
+  test('Core.is.imageSrc', () => {
+    expect(Core.is.imageSrc('https://xxxxx')).toStrictEqual(true);
+    expect(Core.is.imageSrc('http://xxxxx')).toStrictEqual(true);
+    expect(Core.is.imageSrc('./xxxxx/xxx')).toStrictEqual(true);
+    expect(Core.is.imageSrc('/xxxxx/xxx')).toStrictEqual(true);
+    expect(Core.is.imageSrc('data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAOg')).toStrictEqual(true);
+    expect(Core.is.imageSrc('dafafsfsaffafa')).toStrictEqual(false);
+  });
+
+  test('Core.is.imageURL', () => {
+    expect(Core.is.imageURL('https://xxxxx')).toStrictEqual(true);
+    expect(Core.is.imageURL('http://xxxxx')).toStrictEqual(true);
+    expect(Core.is.imageURL('./xxxxx/xxx')).toStrictEqual(true);
+    expect(Core.is.imageURL('/xxxxx/xxx')).toStrictEqual(true);
+    expect(Core.is.imageURL('dafafsfsaffafa')).toStrictEqual(false);
+  });
+
+  test('Core.is.imageBase64', () => {
+    expect(Core.is.imageBase64('data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAOg')).toStrictEqual(true);
+    expect(Core.is.imageBase64('http://xxxxx')).toStrictEqual(false);
+    expect(Core.is.imageBase64('./xxxxx/xxx')).toStrictEqual(false);
+    expect(Core.is.imageBase64('/xxxxx/xxx')).toStrictEqual(false);
+    expect(Core.is.imageBase64('dafafsfsaffafa')).toStrictEqual(false);
+  });
+
+  test('Core.is.svg', () => {
+    expect(Core.is.svg(`
+      <svg t="12231231">
+        <g></g>
+      </svg>
+      `)).toStrictEqual(true);
+      expect(Core.is.svg(`
+      <svg>
+        <g></g>
+      </  svg>
+      `)).toStrictEqual(true);
+    expect(Core.is.svg('./xxxxx/xxx')).toStrictEqual(false);
+    expect(Core.is.svg('/xxxxx/xxx')).toStrictEqual(false);
+    expect(Core.is.svg('dafafsfsaffafa')).toStrictEqual(false);
+  });
+
+  test('Core.is.text', () => {
+    expect(Core.is.text('abcdefg123456')).toStrictEqual(true);
+    expect(Core.is.text('')).toStrictEqual(true);
+    expect(Core.is.text(123)).toStrictEqual(false);
+  });
+
+  test('Core.is.fontSize', () => {
+    expect(Core.is.fontSize(12)).toStrictEqual(true);
+    expect(Core.is.fontSize(0)).toStrictEqual(false);
+    expect(Core.is.fontSize(-10)).toStrictEqual(false);
+  });
+
+  test('Core.is.lineHeight', () => {
+    expect(Core.is.lineHeight(12)).toStrictEqual(true);
+    expect(Core.is.lineHeight(0)).toStrictEqual(false);
+    expect(Core.is.lineHeight(-10)).toStrictEqual(false);
+  });
+
+  test('Core.is.textAlign', () => {
+    expect(Core.is.textAlign('center')).toStrictEqual(true);
+    expect(Core.is.textAlign('left')).toStrictEqual(true);
+    expect(Core.is.textAlign('right')).toStrictEqual(true);
+    expect(Core.is.textAlign('helloworld')).toStrictEqual(false);
+  });
+
+
+  test('Core.is.fontFamily', () => {
+    expect(Core.is.fontFamily('yahei')).toStrictEqual(true);
+    expect(Core.is.fontFamily('helloworld')).toStrictEqual(true);
+    expect(Core.is.fontFamily('')).toStrictEqual(false);
+  });
+
 })
\ No newline at end of file
diff --git a/packages/core/src/index.ts b/packages/core/src/index.ts
index 2b6c356..b6a010b 100644
--- a/packages/core/src/index.ts
+++ b/packages/core/src/index.ts
@@ -60,8 +60,8 @@ class Core {
   private [_prevPoint]: TypePoint | null = null;
   private [_selectedDotDirection]: TypeHelperWrapperDotDirection | null = null;
 
-  static is = is;
-  static check = check;
+  static is: any = is;
+  static check: any = check;
 
   constructor(mount: HTMLDivElement, opts: TypeCoreOptions, config?: TypeConfig) {
     this[_data] = { elements: [] };
diff --git a/packages/core/src/lib/check.ts b/packages/core/src/lib/check.ts
index acdd5e4..d536a0f 100644
--- a/packages/core/src/lib/check.ts
+++ b/packages/core/src/lib/check.ts
@@ -1,9 +1,7 @@
 
-import { TypeElementAttrs} from '@idraw/types';
-import util from '@idraw/util';
+import { TypeElementAttrs } from '@idraw/types';
 import is from './is';
 
-const { isColorStr } = util.color;
 
 function attrs(
   attrs: TypeElementAttrs
@@ -22,10 +20,10 @@ function rectDesc(
   desc: any
 ): boolean {
   const { borderColor, borderRadius, borderWidth, color } = desc;
-  if (typeof borderColor === 'string' && !isColorStr(color)) {
+  if (typeof borderColor === 'string' && !is.color(color)) {
     return false;
   }
-  if (typeof borderColor === 'string' && !isColorStr(borderColor)) {
+  if (typeof borderColor === 'string' && !is.color(borderColor)) {
     return false;
   }
   if (typeof borderRadius === 'number' && !is.number(borderRadius)) {
@@ -41,5 +39,6 @@ const check = {
   attrs,
   rectDesc,
 }
+ 
 
 export default check;
\ No newline at end of file
diff --git a/packages/core/src/lib/is.ts b/packages/core/src/lib/is.ts
index 7ed2702..5b96c46 100644
--- a/packages/core/src/lib/is.ts
+++ b/packages/core/src/lib/is.ts
@@ -1,3 +1,6 @@
+import util from "@idraw/util";
+
+const { isColorStr } = util.color;
 
 function number(value: any) {
   return (typeof value === 'number' && (value > 0 || value <= 0))
@@ -23,8 +26,60 @@ function angle(value: any) {
   return (typeof value === 'number' && value >= -360 && value <= 360)
 }
 
+function borderWidth(value: any) {
+  return w(value);
+}
+
+function borderRadius(value: any) {
+  return number(value) && value >= 0;
+}
+
+function color(value: any) {
+  return isColorStr(value);
+}
+
+function imageURL(value: any) {
+  return (typeof value === 'string' && /^(http:\/\/|https:\/\/|\.\/|\/)/.test(`${value}`))
+}
+
+function imageBase64(value: any) {
+  return (typeof value === 'string' && /^(data:image\/)/.test(`${value}`))
+}
+
+function imageSrc(value: any) {
+  return (imageBase64(value) || imageURL(value))
+}
+
+function svg(value: any) {
+  return (typeof value === 'string' && /^(<svg[\s]{1,}|<svg>)/i.test(`${value}`.trim()) && /<\/[\s]{0,}svg>$/i.test(`${value}`.trim()));
+}
+
+function text(value: any) {
+  return typeof value === 'string';
+}
+
+function fontSize(value: any) {
+  return number(value) && value > 0;
+}
+
+function lineHeight(value: any) {
+  return number(value) && value > 0;
+}
+
+function textAlign(value: any) {
+  return ['center', 'left', 'right'].includes(value);
+}
+
+function fontFamily(value: any) {
+  return typeof value === 'string' && value.length > 0;
+}
+
+
 const is = {
   x, y, w, h, angle, number,
+  borderWidth, borderRadius, color,
+  imageSrc, imageURL, imageBase64, svg,
+  text, fontSize, lineHeight, textAlign, fontFamily,
 }
 
 export default is;
\ No newline at end of file
diff --git a/packages/types/src/lib/element.ts b/packages/types/src/lib/element.ts
index a9016ec..e0fd436 100644
--- a/packages/types/src/lib/element.ts
+++ b/packages/types/src/lib/element.ts
@@ -24,7 +24,7 @@ type TypeElemBoxDesc = {
 type TypeElemDesc = {
   text: TypeElemDescText,
   rect: TypeElemDescRect,
-  circle: TypeElemDescCircle,
+  // circle: TypeElemDescCircle,
   image: TypeElemDescImage,
   svg: TypeElemDescSVG,
   // paint: TypeElemDescPaint,
@@ -44,11 +44,11 @@ type TypeElemDescText = {
   textAlign?: 'center' | 'left' | 'right';
 } & TypeElemBoxDesc
 
-type TypeElemDescCircle = {
-  r: number;
-  x: number;
-  y: number;
-}
+// type TypeElemDescCircle = {
+//   r: number;
+//   x: number;
+//   y: number;
+// }
 
 type TypeElemDescImage = {
   src: string;
@@ -64,7 +64,7 @@ export {
   TypeElementAttrs,
   TypeElemDescText,
   TypeElemDescRect,
-  TypeElemDescCircle,
+  // TypeElemDescCircle,
   TypeElemDescImage,
   TypeElemDescSVG,
   TypeElemDesc,
diff --git a/packages/util/src/lib/color.ts b/packages/util/src/lib/color.ts
index dd1f290..baa61b1 100644
--- a/packages/util/src/lib/color.ts
+++ b/packages/util/src/lib/color.ts
@@ -7,5 +7,5 @@ export function toColorHexStr(color: number): string {
 }
 
 export function isColorStr(color?: string): boolean {
-  return  typeof color === 'string' && /^\#[0-9a-z]{3,8}$/i.test(color);
+  return  typeof color === 'string' && /^\#([0-9a-f]{3}|[0-9a-f]{6}|[0-9a-f]{8})$/i.test(color);
 }
\ No newline at end of file